Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Chemistry > Unit 1.3 - Chemical Calculations > Flashcards

Unit 1.3 - Chemical Calculations Flashcards

1
Q

Relative atomic mass symbol

A

Ar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Why can atoms not be weighed?

A

They’re too small

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What do we do as atoms are too small to be weighed?

A

Compare them to a standard - the C-12 isotope

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the standard we compare atoms to?

A

The Carbon 12 isotope

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What’s the mass of C-12 isotopes?

A

12 units

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What can atoms of the same element have due to the existence of isotopes?

A

Different masses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What do we have to do to define relative atomic masses due to the existence of isotopes?

A

Take an “average” mass of the atoms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Does relative atomic mass (Ar) have units? Why?

A

No, as they’re ratios of units

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What do all of the “relative….mass” definitions have reference to?

A

The C-12 isotope

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Relative atomic mass (Ar)

A

The ratio of the average mass of an atom of the natural nuclidic composition of the element to 1/12 of the mass of an atom of the C-12 isotope

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Relative isotopic mass

A

The ratio of the average mass of an atom of the element to 1/12 of the mass of an atom of the C-12 isotope

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Relative molecular mass symbol

A

Mr

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Relative molecular mass (Mr)

A

The ratio of the mass of a molecule of a chemical compound to 1/12 of the mass of an atom of the C-12 isotope

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How do you calculate the relative molecular mass (Mr)?

A

Add up all of the relative atomic masses (top numbers), multiplying only by the small numbers and ignoring big ones, using the molecular formula

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How are relative formula mass and relative molecular mass the same?

A

-Same definition
-Same symbol (Mr)
-Same calculation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How is relative formula mass different to relative molecular mass?

A

Relative molecular mass = Molecular formula
Relative formula mass = Empirical formula

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What do we measure the amount of a substance in?

A

Moles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Mole

A

One mole is the amount of a substance which contains the same number of particles as there are atoms in 12g of the C-12 isotope

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is Avogadro’s Constant?

A

The number of atoms in one mole of an element

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Avogadro’s constant symbol

A

NA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the number of atoms in one mole of an element?

A

Avogadro’s constant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

How do we calculate the mass of 1 mole of an element in grams

A

Ar in grams (super easy!)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What’s the ratio of the average mass of an atom of the natural nuclidic composition of the element to 1/12 of the mass of an atom of the C-12 isotope?

A

Relative atomic mass (Ar)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What’s the ratio of the average mass of an atom of an element to 1/12 of the mass of an atom of the C-12 isotope?

A

Relative isotopic mass

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What’s the ratio of the mass of a molecule of a chemical compound to 1/12 of the mass of an atom of the C-12 isotope?

A

Relative formula mass (Mr)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What’s the amount of a substance which contains the same number of particles as there are atoms in 12g of the C-12 isotope?

A

A mole

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What does the mass spectrometer do?

A

Accurately measures relative atomic masses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What do we obtain from a mass spectrometer?

A

A mass spectra, which has a wide variety of uses in labs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What’s the order of the processes that take place within the mass spectrometer?

A

-Vaporisation
-Ionisation
-Acceleration
-Deflection
-Detection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Where does the vaporised sample enter in order to be ionised in the mass spectrometer?

A

The ionisation chamber

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Why must our sample into the mass spectrometer be vaporised?

A

You can only ionise vapour

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

How does the ionisation stage within the mass spectrometer work?

A

The electron gun gives out high energy electrons, which knock the electron out of an atom in the gaseous sample due to its speed, thus ionising them

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Why is ionisation necessary in the mass spectrometer in order to accurately measure relative atomic masses?

A

-Only ions will create a current when hitting the detector
-We want ions, not molecules to interact with the magnetic field

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What happens during the acceleration stage to ions within the mass spectrometer?

A

They’re sped up by a magnetic field until they’re all at the same speed into a finely focused beam

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

How are ions sped up in the mass spectrometer?

A

By a magnetic field

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Until when are the ions sped up in a mass spectrometer?

A

Until they’re all travelling at the same speed into a finely focused beam

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Draw and label the mass spectrometer

A

(Check notes)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What’s the purpose of the vacuum pump on the mass spectrometer?

A

To prevent the ions colliding with air molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What are ions deflected by in the mass spectrometer?

A

A magnetic field (an electromagnet)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What is at the detection stage of the mass spectrometer?

A

-Amplifier
-Chart recorder

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Why is it the MASS that impacts how much the ions are deflected by the electric field of the electromagnet in a mass spectrometer?

A

As the ions are all equal charge so this doesn’t effect it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

What are ions deflected according to in a mass spectrometer?

A

Their mass/charge ratio

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

If an ion is lighter, how does this effect how it’s deflected?

A

Deflected more

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

What type of ions reach the detector first in a mass spectrometer?

A

The lighter ones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Which ions have the lowest m/z value in a mass spectrometer?

A

The lightest ones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

What happens to ions with different mass to charge ratios in the mass spectrometer?

A

They’re deflected and measured separately

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

What do we look at for an ions m/z number?

A

Its mass number

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Mass to charge ratio symbol

A

m/z or m/e

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

List what happens at the detection stage on the mass spectrometer

A

-Beam of ions detected electrically
-Electric current = amplified + recorded
-More ions = more current
-Results analysed by a computer and displayed on the visual display unit of the computer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

How does the amount of ions effect the current in a mass spectrometer?

A

More ions = higher current

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

How are the results from a mass spectrometer analysed on a computer?

A

Displayed on the visual display unit of the computer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

What two things do we need to know in order to calculate the relative atomic masses of elements?

A
  • The relative isotopic mass (top number)
    -The relative abundance of the isotopes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

Relative abundance

A

The fraction of that isotope found in the natural nuclidic composition of the element

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

What’s the fraction of an isotope found in the natural nuclidic composition of an element?

A

Its relative abundance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

What’s the formula for calculating the relative atomic mass of an element?

A

(%abundance X isotopic mass of element - top number) + (next one) + (next one) …
———————————————————————————————————————
100

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

How can we confirm if the relative atomic mass that we’ve calculated is correct?

A

Is says it on the periodic table (the top number)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

What do we need to do if the abundance given to us for a relative atomic mass formula is in decimals?

A

We do NOT have to divide it by 100

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

What do we do if relative abundance isn’t given in decimals or percentages and simply as a number?

A

Add them together and divide by this total

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

What’s the highest possible relative abundance?

A

100%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

What’s relative abundance (simply)?

A

How much of that isotope is in that element

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

What’s goes along the x and y axis on a graph for calculating relative atomic mass?

A

X - mass/charge (m/z)
Y - relative abundance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

What’s really important to show on the isotopes we’re using for relative atomic mass calculations?

A

Their charges

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

What do we do if peak height is given instead of relative abundance to calculate the relative atomic mass?

A

Relative abundance = peak height
——————
Total height

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

Equation for the ionisation of Cl-35 in the mass spectrometer

A

Cl2 (g) + e- ——> Cl2+ (g) +2e-

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

Equation for the ionisation of Chlorine

A

Cl2 (g) + e- ——> Cl2+ (g) + 2e-

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

What can molecular ions do in the mass spectrometer?

A

Undergo fragmentation to give us monatomic chlorine ions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

What does the fragmentation of chlorine molecular ions give us?

A

Monatomic chlorine ions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

Why does fragmentation happen to molecular chlorine ions in the mass spectrometer?

A

Due to the instability of Cl2+ ions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

What ions does Chlorine come out as out of the ionisation chamber and what’s wrong with this?

A

Cl2+ are unstable = undergo fragmentation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

Fragmentation

A

the dissociation of energetically unstable molecular ions formed from passing the molecules in the ionization chamber of a mass spectrometer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

Chlorine Cl2+ ions fragmentation equation

A

Cl2+ (g) ——> Cl+ (g) + Cl (g)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

How many isotopes does chlorine have and what are they?

A

Two
35Cl
37Cl

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

What is the abundance of the Cl35 Chlorine isotope in its natural nuclidic composition?

A

75%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

What is the abundance of the Cl37 Chlorine isotope in its natural nuclidic composition?

A

25%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

What is the ratio in the atomic ion region of chlorine?

A

3:1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
76
Q

What gives us the molecular ion region on chlorines graph?

A

The fact that chlorine exists as a diatomic molecule - it consists of molecules, not individual atoms (think of the possible combinations of Cl35 and Cl37)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
77
Q

What type of molecule does chlorine exist as and what does this give us?

A

Diatomic, giving us the molecular ion region on the graph

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
78
Q

What are the two ion regions we have o chlorine’s mass spectrum?

A

-atomic ion region
-molecular ion region

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
79
Q

What do we call the graph with relative abundance and m/z?

A

The mass spectrum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
80
Q

What does chlorine’s atomic ion region peak in?

A

3:1 ratio

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
81
Q

What does chlorine’s molecular ion region peak in?

A

9:6:1 ratio

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
82
Q

Which molecular ions do we have for chlorine?

A

M/z = m70, m72 and m74

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
83
Q

What’s the possibility of an atom being 35Cl?

A

3/4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
84
Q

What’s the possibility of an atom being 37Cl?

A

1/4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
85
Q

How do we get the fractions for figuring out the ratio of the molecular ion region on chlorine’s mass spectrum?

A

Multiply the possibility of getting each isomer
E.g - 35Cl-35Cl
3/4 x 3/4
= 9/16
(The 9 in the ratio)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
86
Q

What’s it important to do with all of the fractions when working out the ratio of a molecular ion region?

A

Keep them relative (same bottom number) so as to get the correct ratio - the calculator might simplify!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
87
Q

What do we do if we’re asked to work out the percentage of an isotope in a molecule, or the mass number?

A

Use algebra - the same method as before with the relative atomic mass but with an ‘x’ where relevant - remember you can find the relative atomic mass for the start of the equation on the periodic table

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
88
Q

How do you work out the ratio of the molecular ion region of an element?

A

Multiply the possibilities of getting each isotope (abundance) with it’s possible pair - make sure all fractions have the same bottom number
(Check notes for chlorine example, it’ll look confusing here)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
89
Q

What isotopes does Bromine have?

A

79Br and 81Br

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
90
Q

What is the ratio of 79Br and 81Br isotopes in a Bromine molecule?

A

50:50

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
91
Q

How many peaks does a diatomic molecule have on its mass spectrum? How do we know this?

A

5
Think - we have 2 isotopes, which is 2 peaks in the atomic ion region
Then, we have 3 different possibilities of combinations of these isotopes for the molecular ion region = 3 more peaks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
92
Q

How many peaks does Bromine’s mass spectrum have?

A

5

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
93
Q

Which diatomic molecules do we need to remember their mass spectrums and why they look like this (know the ratios, abundances, isotopes e.t.c.)?

A

Mostly Chlorine, an idea of Bromine too

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
94
Q

Empirical formula

A

The simplest ratio of atoms in the molecule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
95
Q

Molecular formula

A

The actual number of each atom present in the molecule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
96
Q

How do we calculate the relative molecular mass?

A

Sum of Ar’s in the molecule (multiply only by the little numbers, ignoring the big ones)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
97
Q

Relative molecular mass symbol

A

Mr

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
98
Q

Molecular formula of glucose molecules

A

C6H1206

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
99
Q

Molar mass unit

A

gmol-1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
100
Q

Molar mass of glucose molecules

A

180gmol-1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
101
Q

Empirical formula of glucose molecules (how is this worked out?)

A

CH20
(Molecular formula divided by 6)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
102
Q

What do we do if working out the empirical formula from a diagram?

A

Ignore ions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
103
Q

Are ions part of empirical formulas?

A

No

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
104
Q

What do we have to know in order to calculate empirical formulas?

A

The % composition by mass of each element in the molecule in order to divide it by their relative atomic masses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
105
Q

Steps in working out Empirical formulas

A
  1. Write symbols of elements
  2. Write masses/percentages from the question
  3. Divide each mass/percentage by the mass number of that element (Ar)
  4. Divide each answer with the smallest answer to find the ratio
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
106
Q

Do we ever round up or down when working out empirical formulas?

A

No, instead we multiply them up if the ratios are in decimals (individual elements)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
107
Q

What would you multiply a 0.2 decimal in a ratio for an empirical formula by?

A

5

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
108
Q

What would you multiply a 0.3 decimal in a ratio for an empirical formula by?

A

3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
109
Q

What would you multiply a 0.5 decimal in a ratio for an empirical formula by?

A

2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
110
Q

What do we have to know in order to work out the molecular formula of a molecule?

A

The relative molecular mass

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
111
Q

How do we calculate the molecular formula of a molecule?

A
  1. Determine the relative mass of empirical formula
    (Add up the Ar numbers, multiplying only by the small numbers and ignoring the big ones)
  2. Divide the Mr (given in question) by mass of empirical formula (our last answer) to get a multiple
  3. Multiply empirical formula by the multiple
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
112
Q

How do we determine the relative mass of an empirical formula?

A

Add up all of the Ar numbers (relative atomic masses of the atoms), multiplying only by the small numbers and ignoring the big ones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
113
Q

What’s the most likely mass of a chlorine molecule?

A

70

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
114
Q

Define the mole

A

The standard unit (an SI unit) for the amount of a substance, which is Avogadro’s constant (NA)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
115
Q

Avogadro’s constant symbol

A

NA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
116
Q

Simple way of defining the mole in terms of particles

A

One mole has (Avogadro constant) amount of atoms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
117
Q

What type of quantity is molar mass and what does this mean for it?

A

A physical quantity, therefore it has units

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
118
Q

Molar mass units (Mr)

A

gmol-1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
119
Q

Define the molar mass of an element

A

The mass of one mole of the element in grams

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
120
Q

What is molar mass equal to?

A

Mr

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
121
Q

Triangle showing the relationship between molar mass, mass and amount of moles

A

m
—
n I M

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
122
Q

What does M stand for?

A

Molar mass

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
123
Q

What does m stand for?

A

Mass

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
124
Q

What does n stand for?

A

Amount in moles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
125
Q

Amount in moles unit

A

Mol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
126
Q

What do we use as our molar mass in equations and when?

A

If we get no information on the moles or mass, make the molar mass equal to the Mr

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
127
Q

Number of particles/atoms formula

A

Number of moles x NA
(Remember - this can be rearranged!)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
128
Q

Number of particles unit

A

It doesn’t have one

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
129
Q

What is necessary in calculations such as ones discovering the number of particles?

A

Combining both the molar mass, mass, moles triangle equation and the number of particles, moles and NA one

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
130
Q

What do the same conditions of temperature and pressure cause any gas to do?

A

Occupy the same volume

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
131
Q

What conditions are require to be kept the same for one mole of any gas to occupy the same volume?

A

Temperature
Pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
132
Q

When does one mole of any gas occupy the same volume?

A

Under the same conditions of temperature and pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
133
Q

How much of any gas will occupy the same volume under the same conditions of temperature and pressure?

A

1 mole

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
134
Q

What is the molar volume of a gas?

A

Under the same conditions of temperature and pressure, one mole of any gas will occupy the same volume

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
135
Q

What’s the name for the fact that under the same conditions of temperature and pressure, one mole of any gas will occupy the same volume?

A

Molar volume

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
136
Q

Stp

A

Standard temperature and pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
137
Q

What is the standard temperature and pressure?

A

273K
1 atm (1.01x10^5 Pa)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
138
Q

What is 1 atm?

A

1.01 x10^5 Pa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
139
Q

22.4dm^3 in litres

A

22.4 litres (the same)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
140
Q

What’s the difference between the two molar volumes given in the data sheet?

A

Different temperatures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
141
Q

What happens to a gas with increased temperature, providing that the pressure remains constant?

A

Gas occupies a bigger volume

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
142
Q

When does a gas occupy a bigger volume?

A

With increased temperature, providing that the pressure remains constant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
143
Q

What do we need to check before answering any of the questions surrounding molar volume?

A

The temperature, to get our molar volume based off of information on the data sheet

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
144
Q

Volume unit

A

dm^3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
145
Q

Moles unit

A

Mol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
146
Q

Triangle for the equations on molar volume

A

V
—
n I Vm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
147
Q

Amount in moles symbol

A

n

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
148
Q

Volume symbol

A

V

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
149
Q

Molar volume symbol

A

Vm

150
Q

How do we transfer between cm^3 and dm^3?

A

cm^3 ———> dm^3
÷1000

151
Q

What does the volume always have to be in molar volume questions?

A

dm^3

152
Q

How do we figure out how much one mole of an element is?

A

Ar in grams (super easy)

153
Q

What do we do if a molar volume question gives us the temperature in degrees Celsius?

A

Add 273 to the number and it’ll be in Kelvin
(It says this on the front of the data sheet though)

154
Q

How do we know whether to combine the molar volume equations with the molar mass equations?

A

Just think of the information that we have - for example, if it’s asking us to calculate the mass with data on the moles, use the molar mass equations, but if we’re given the volume, we need to use the molar volume equation for the amount of moles and then use the molar mass equations to go back to the mass - I’ve made it sound really confusing. Just think what equations you know and what information you have and what makes sense together - you’ll get it.

155
Q

What do you call the solution that moles are in?

A

Concentration

156
Q

Concentration

A

How much of a dissolved substance is present per unit volume of a solution (number of moles in 1dm^3)

157
Q

How many dm^3 and cm^3 is one litre?

A

1 dm^3
1000cm^3

158
Q

How many litres and dm^3 is 1000cm^3?

A

1 litre
1 dm^3

159
Q

How many cm^3 and litres is 1 dm^3?

A

1000cm^3
1 litre

160
Q

What is the main solvent used in chemistry?

A

Water

161
Q

What is concentration measured in?

A

gdm^-3 OR moldm^-3

162
Q

How do we convert between gdm^3 and moldm^3?

A

gdm^-3
——-————
moldm^-3 I Mr

163
Q

Moles in solution equations

A

n
—
c I V

164
Q

Shorthand of moldm^-3

A

M

165
Q

What is “M” the shorthand of?

A

Concentration (moldm^-3)

166
Q

What is the mass to charge ratio (m/z) equal to and when?

A

When the ions generated by a mass spectrometer have a 1+ charge (like chlorine!), it’s equal to the atomic mass of the element

167
Q

Concentration in parts per million (ppm) equation

A

Mass solute
—————— x1,000,000
Mass Solution

168
Q

When do we take into account the big numbers of a molecule and when don’t we?

A

Molecular = ignore big numbers
Formula = use big numbers
(Mr)

169
Q

What are the masses of the molecular ion region in the mass spectrum of chlorine?

A

70, 72 and 74

170
Q

What are the masses in the molecular ion region on the mass spectrum of Bromine?

A

158, 160, 162

171
Q

Show algebraically the relationship between the amount of moles o A, B, C and D involved in a reaction

A

nA nB. nC nD
— = — = — = —
a. b. c. d.

172
Q

What does the algebratic equation between nA, nB, nC and nD show?

A

The amount in moles of A, B, C and D respectively involved in the reaction

173
Q

What’s the reaction between sodium hydroxide and hydrogen chloride?

A

NaOH + NCl ———> NaCl + H20

174
Q

How can we see if different elements have the same number of moles as each other or not?

A

Look at the big numbers - the same = same number of moles

175
Q

What do we need to be given to calculate the mass of the products formed?

A

-Mass of reactants
-A balanced chemical equation

176
Q

What happens in a chemical reaction?

A

Reactants are changing into products

177
Q

Ratio between amount of moles of reactants and products

A

Stoichiometric ratios (mole ratios)

178
Q

Stoichiometric ratios

A

Ratio between the amount of moles of reactants and products (mole ratios)

179
Q

Do we multiply with the big numbers for molar mass (Mr)?

A

NO

180
Q

What do we need to avoid doing in reacting masses calculations?

A

Over-round a figure too early on in the calculation (accuracy marks!!)

181
Q

What do we do if asked to work out the identity of an element after we’ve figured out its mass?

A

Just match it with that relative atomic mass off of the periodic table

182
Q

1 tonne in kilograms

A

1000kg

183
Q

1000kg in tonnes

A

1 tonne

184
Q

What do we do if we have an unknown mass and don’t have the moles or molar mass to work it out?

A

Total mass of reagents = total mass of products
e.g -
0.800g of M(OH)2 ——> 0.553g of MO + ?g of H20
0.800-0.553 = 0.247g

185
Q

What is one of the main aims in green chemistry?

A

To reduce pollution created in a chemical reaction

186
Q

What happens when a large proportion of a reagent ends up as waste? (3 things)

A

-Pollution contribution
-Ineffective use of resources
-Raise in production costs

187
Q

What contributes to pollution, ineffective use of resources and a raise in production costs?

A

Large proportions of reagents ending up a waste

188
Q

Atom economy

A

A measure of the amount of starting materials that become useful products

189
Q

What is a measure of the amount of starting materials that become useful products?

A

Atom economy

190
Q

Atom economy equation

A

Atom economy (%) = mass of useful product from equation
——————————————————— x100
Mass of reagents from equation

191
Q

What do insufficient, wasteful processed have?

A

A low atom economy

192
Q

What have low atom economies?

A

Insufficient, wasteful processes

193
Q

What do efficient processes have?

A

High atom economies

194
Q

What have high atom economies?

A

Efficient processes

195
Q

What are efficient, high atom economy processes important for?

A

Sustainable development - fewer resources, less waste

196
Q

What is the ideal atom economy and what would this actually mean?

A

100% - no waste products, everything is useful products

197
Q

Do we take into account the big numbers for Mr when working out atom economies?

A

(Sigh) - yes.

198
Q

In what equations do we take into account the big numbers for Mr?

A

Atom economy equations

199
Q

Why is hydrogen a useful product?

A

Hydrogen fuel cells make electricity, with the only product being water

200
Q

Name 2 non-renewable sources

A

Coal
Methane

201
Q

What type of sources are coal and methane?

A

Non-renewable

202
Q

% yield equation

A

% yield = actual mass of product obtained
————————————————
Theoretical yield

203
Q

How does percentage yield working out start?

A

Very similar to to reacting masses sums - underline what’s important, work out the masses through comparing molar ratios etc, but use the formula at the end

204
Q

Do we take into account the big numbers for Mr with percentage yields?

A

No

205
Q

Give 2 reasons why a % yield wouldn’t be at 100%

A

-Some reactants not fully reacting
-Formation of side products (especially oxygen, which often reacts with reagents)

206
Q

Which element often reacts with reagents?

A

Oxygen

207
Q

Do you use the big numbers (molar ratios) in atom economy and percentage yields?

A

Atom economy - yes
Percentage yields - no

208
Q

Is it possible for atom economy to be above 100%?

A

No

209
Q

What do we do if a question states that something is ‘burning in air’?

A

Put it down as reacting with oxygen to create an oxide

210
Q

What is the ratio of in empirical and molecular formulas?

A

Moles - in a more complex question, remember that’s what we’re trying to get the ratio of! Use the formula!

211
Q

What do we do with the multiples we receive when figuring out the relative formula of a compound?

A

Don’t round them up - only round up the final molecular formula

212
Q

How do you calculate the number of molecules in a sample?

A

Moles (n = m x Na (Avogadro’s number)
—
M)

213
Q

How do you calculate the number of atoms in a sample?

A

Number of molecules x number of individual elements (e.g - SOCL2 has 4)

214
Q

What do we need to remember with empirical formula?

A

Divide down to the SIMPLEST ratio of atoms in the molecule

215
Q

Boyle’s law

A

PV=constant
Product of pressure and volume is a constant
-At a constant temperature, the volume of a fixed gas is inversely proportional to its pressure

216
Q

Which law is PV = constant?

A

Boyle’s law

217
Q

Charles’ law

A

V
— = constant
T

The volume of gas is constant as long as the pressure remains constant

218
Q

Which law is V
— = constant?
T

A

Charles’ law

219
Q

Gay-Lussac’s law

A

P
— = constant
T

The pressure is proportional to the temperature as long as the volume remains constant

220
Q

Which law is P
— = constant
T

A

Gay-Lussac’s law

221
Q

What has to remain constant for Boyle’s law?

A

Temperature

222
Q

What has to remain constant for Charles’ law?

A

Pressure

223
Q

What has to remain constant for Gay-Lussac’s law?

A

Volume

224
Q

How did we get the gas constant and what is its symbol?

A

Combining Boyle’s, Charles’ and Gay-Lussac’s laws gives…

PV
— = constant for a fixed mass of gas (R)
T

So, PV=RT (for 1 mole of gas)

225
Q

What is the ideal gas equation?

A

PV = nRT

226
Q

Does every gas obey the ideal gas equation?

A

No gas obeys it entirely

227
Q

Under what conditions does the ideal gas equation hold quite well?

A

Room temperature and pressure

228
Q

Under room temperature and pressure, what holds quite well?

A

The ideal gas equation

229
Q

2 features of an ideal gas

A

-All collisions between atoms or molecules are perfectly elastic
-No intermolecular attraction forces

230
Q

What would having all collisions between atoms or molecules perfectly elastic and no intermolecular attraction forces give us?

A

An ideal gas

231
Q

Perfectly elastic collisions between atoms or molecules

A

All energy is transferred - no loss of energy

232
Q

If there’s no loss of energy and all is transferred during a collision between atoms or molecules, describe the collision

A

Perfectly elastic

233
Q

SI units used with the ideal gas equation

A

Pressure - Pa
Volume - m^3
Temperature - K

234
Q

What’s the first thing we do before anything else when dealing with the ideal gas equation questions?

A

Convert into the SI units

235
Q

Standard pressure

A

1.10x10^5
(Data booklet)

236
Q

atm ——> Pa

A

x1.10x10^5
(data booklet)

237
Q

kPa ——> Pa

A

x1000

238
Q

dm^3 to m^3

A

divided by 1000

239
Q

cm^3 to m^3

A

Divided by 1,000,000

240
Q

Degrees Celsius to kelvin

A

Celsius + 273
(on data booklet)

241
Q

Standard temperature

A

273K
(data booklet)

242
Q

What can 273K be described as?

A

Standard temperature

243
Q

What can 1.01x10^5 be described as?

A

Standard pressure

244
Q

What’s an alternative use for the ideal gas equation?

A

Calculating the volume a gas would occupy at temperatures and volumes other than those it was originally measured at

245
Q

Equation for calculating the volume a gas would occupy at temperatures and pressures other than those it was originally measured at

A

P1V1 P2V2
—— = ——
T1 T2

246
Q

What is the following equation used for?

P1V1 P2V2
—— = ——
T1 T2

A

Calculating the volume a gas would occupy at temperatures and pressures other than those it was actually measured at

247
Q

Evolved

A

Created

248
Q

What is titration an example of?

A

Quantitative analysis

249
Q

Quantitative analysis

A

Uses statistics

250
Q

What type of analysis uses statistics?

A

Quantitative analysis

251
Q

When are titrations used?

A

When two solutions can be reacted and we want to determine the concentration of an identified solution

252
Q

What type of apparatus do we have to use for titrations?

A

Accurately calibrated

253
Q

Summarise the process of a titration

A

Take a fixed volume of a solution with a known concentration
React it with a solution with an unknown concentration
With an accurately measured volume needed to react, we can determine the solution’s concentration

254
Q

What are the apparatus required for titrations?

A

Electronic balance
Gravitated/volumetric flask
Pipette
Burette

255
Q

Two names for the type of flask used during titrations

A

Graduated/volumetric

256
Q

What can an electronic balance weigh to within?

A

+-0.001g

257
Q

What type of facility do most electronic balances have?

A

“Tare” facilities

258
Q

What do we do with an electronic balance with a “tare” facility?

A

-Place beaker on the balance (tared)
-Required amount is placed into the beaker
-Amount weighed should be inside a specified range

259
Q

What should the amount of a substance weighed on an electronic balance be?

A

Within a specified range

260
Q

What’s the name of the balance on an electronic balance?

A

Tared

261
Q

Tared

A

The balance on an electronic balance

262
Q

What happens within the graduated/volumetric flask?

A

Make a solution of known concentration (a standard solution)

263
Q

Standard solution

A

Solution of known concentration

264
Q

Solution of known concentration

A

Standard solution

265
Q

How is a solution of known concentration generated within the volumetric flask?

A

-Exact quantity of solid is weighed and dissolved in water
-Solution is placed in the graduated flask using a funnel
-Beaker is rinsed at least twice (add the water from the rinsing into the flask too)
-Add water to the flask until it reaches the mark
-Invert the flask a number of times to ensure complete mixing

266
Q

How do we ensure complete mixing within the graduated/volumetric flask?

A

Invert a few times

267
Q

How is solution placed into a graduated flask?

A

Using a funnel

268
Q

What’s a pipette used for during titrations?

A

To get samples from the graduated flask - measures an exact volume of liquid

269
Q

What must we use when filling up a pipette?

A

A pipette filler (take care when fitting it - see the instructions sheet)

270
Q

What should always be forbidden in terms of pipettes?

A

Mouth pipetting

271
Q

How much should the pipette be filled with liquid?

A

A little past the 25cm3 mark (the level drops slightly when removed which could give an inaccurate volume)

272
Q

Important things to do when using a pipette

A

-Slowly and carefully to avoid bubbles
-Use a pipette filler

273
Q

Why must the pipette be filled slightly past the 25cm3 mark?

A

The level drops slightly when removed from the liquid - inaccurate volume

274
Q

What’s a burette used for during titrations?

A

Measuring liquid volumes accurately

275
Q

What does a burette usually measure and why?

A

The volume of acid that reacts with alkali, as a base (alkali is a soluble base) can clog it up if left in for too long

276
Q

What are the steps for using a burette during a titration?

A

Initially rinsed with the solution to be placed in it
Solution is placed in burette + initial reading is noted
The titration is carried out
When the reaction is complete, the burette reading is noted again

277
Q

Tolerance of a burette

A

+-0.05cm3

278
Q

How do you read the measurements on a burette?

A

-From the top down
-From the bottom of the miniscus

279
Q

What do we do with titration calculations?

A

Use the same method as reacting masses (molar ratios etc)

280
Q

What’s it really important not to do too early on with moles?

A

Over-round

281
Q

What’s the name for the volume used during the titration?

A

Titre

282
Q

Volume used during a titration

A

Titre

283
Q

What is the first titre?

A

A rough titration

284
Q

How do we calculate the volume used during a titration (titre)?

A

2nd - 1st burette reading

285
Q

What can we do for the next titres after carrying out our rough titration and why?

A

Add the acid drop by drop, as we now have an idea of the titre

286
Q

Concordent

A

Closeness of values

287
Q

Closeness of values

A

Concordant

288
Q

What do the volumes used/titres need to be within of each other in order to be concordant?

A

0.2cm3

289
Q

To how many decimal places do we measure…
i) Volume used (titre)
ii) Mean reading

A

i) 2 d.p
ii) 3 d.p

290
Q

How do we keep the burette level?

A

Clamp it

291
Q

Why do we clamp the burette?

A

To keep it level

292
Q

What’s in the conical flask underneath the burette?

A

Stuff (usually bases) measured by the pipette (exactly 25cm3) + indicator

293
Q

What’s underneath the conical flask during a titration and why?

A

A white tile to easily see the colour change of the indicator

294
Q

What does the indicator in the conical flask during a titration indicate?

A

The end of a titration
(The same number of acids and bases reacting)

295
Q

What’s happened at the end of a titration?

A

The same number of acids and bases are reacting

296
Q

How much indicator should we add to the stuff in the conical flask (usually bases) and why?

A

Only a few drops as it’s a weak acid and so it could give us inaccurate results

297
Q

What could the fact that an indicator is a weak acid lead to?

A

Inaccurate results

298
Q

What is usually the stuff in the conical flask and why?

A

Base, as this would clog up the burette if it were switched with the acid and left there too long

299
Q

What do we have to ensure before taking a reading from a burette?

A

Ensure that the jet below the tap has solution in it

300
Q

Where on the meniscus do we take a reading on the burette?

A

The bottom

301
Q

What do we never start at using a burette?

A

Zero

302
Q

What 2 things do we do with the burette after finishing?

A

Rinse with water
Leave the tap open when replacing the burette in the stand so that any liquid can drain

303
Q

What’s the main error caused by using a burette?

A

Overshooting the end point

304
Q

What is overshooting the end point an error with using?

A

A burette during titrations

305
Q

Reaction between sodium hydroxide and hydrochloric acid

A

NaOH + HCl ——> NaCl + H20

306
Q

Reaction between sodium carbonate and hydrochloric acid

A

Na2CO3 + 2HCL ——> 2NaCl + H20 + C02

307
Q

Alkali

A

Soluble bases (usually hydroxide)

308
Q

Soluble bases (usually hydroxide)

A

Alkali

309
Q

Bases

A

All alkali is base (usually oxide)

310
Q

All are base (usually hydroxide)

A

Alkali

311
Q

Products of reacting an acid with an alkali

A

Salt and water

312
Q

Products of reacting acid with a base

A

Salt and water

313
Q

Products of reacting acid and a metal

A

Salt and hydrogen

314
Q

Products of reacting acids and a carbonate

A

Salt and water and carbon dioxide

315
Q

Describe the reaction between acid and alkali/a base

A

-Exothermic
-Neutralisation
-No effervescence (fizzing)

316
Q

Word for fizzing

A

Effervescence

317
Q

Effervescence

A

Fizzing

318
Q

Describe the reaction between acid and a metal

A

Effervescence (fizzing)
Exothermic

319
Q

Describe the reaction between acid and a carbonate

A

Effervescence
neutralisation

320
Q

Salt

A

Hydrogen with the atom replaced with metal or ammonium ion e.g -
Sulphuric acid - Sulphate salt
Hydrochloric acid - Chloride salt
Nitric acid - Nitrate salt

321
Q

How are the ions accelerated within the mass spectrometer?

A

Negatively charged plates accelerate positive ions

322
Q

What happens to the volume of a gas at lower temperatures and why?

A

Decreases as the sample changes from gas to a liquid, reducing the volume of gas

323
Q

What is the volume of a gas proportional to?

A

Temperature and pressure

324
Q

Define an ideal gas

A

All collisions between atoms or molecules are perfectly elastic and there’s no intermolecular attractions

325
Q

How do you calculate the percentage by mass of an element in a compound?

A

Mr of element
———————. x100
Mr of compound

326
Q

What mass is a chlorine molecule most likely to have?

A

70

327
Q

Define the mole and Avogadro’s constant

A

One mole is the amount of any substance that contains the same number of particles as here are atoms in exactly 12g of carbon-12
This fixed number is called Avogadro’s constant

328
Q

What’s the volume measured in with the ideal gas equation?

A

metres cubed

329
Q

What’s the equation for general first ionisation?

A

x (g) —> x+ (g) + e-

330
Q

What’s an important concept to remember about emission and absorption spectra?

A

You cannot get an emission spectrum without getting an absorption spectrum first

331
Q

Transition metal

A

An element whose atom has a partially filled d-sub shell

332
Q

An element whose atom has a partially filled d-sub shell

A

Transition metal

333
Q

How do we get an empirical formula from a molecular formula?

A

Divide by the highest common factor

334
Q

Percentage error equation

A

Error
———. x100
Quantity being measured

335
Q

What’s the ‘error’ in the percentage error equation?

A

The precision of which the equipment measures to/tolerance

336
Q

Tolerance

A

The precision of which equipment measures to

337
Q

Word for the precision of which equipment measures to

A

Tolerance

338
Q

What do you do with percentage error if you have more than one piece of equipment?

A

The total error is the sum of the % error for each piece of equipment

339
Q

To how many significant figures do we give our percentage error answer for errors between 0.1% and 1%?

A

3 s.f.

340
Q

Give two ways that percentage error can be reduced

A

Make use of more accurate pieces of equipment
Arrange things so that the measurement itself is bigger

341
Q

Tolerance of a pipette

A

0.05cm^3

342
Q

Tolerance of a burette

A

0.05cm^3

343
Q

What’s the exception for multiplying with big numbers for Mr?

A

a hydrate, for example CuSO4.5H20, where you’d work out the Mr of CuSO4, then the Mr of water and multiply water’s one by 5 and add these together

344
Q

Why would a lid be left on whilst heating during an experiment?

A

Avoid spitting and thus loss of liquid

345
Q

Why would a lid be left on whilst cooling during an experiment?

A

To avoid water being absorbed from the atmosphere

346
Q

What can we do to avoid the problem of not all water being lost in a reaction?

A

Heat to constant mass

347
Q

How many decimetres in a litre?

A

1

348
Q

How many litres in a decimetre?

A

1

349
Q

How do you calculate the number of particles in a sample?

A

Moles x Avogadro’s constant

350
Q

How do we work out the value of X in front of a hydrated compound such as BaCl2.XH2O?

A

Mr of each
Mass of each
Compare moles as ratio

351
Q

How do we know if enough of a reactant has been added to react with ALL of the other reactant by the end of the reaction process?

A

Allow it to settle
Add another few drops to see if precipitate still forms

352
Q

If we get 0.6 in empirical and molecular formulae questions, what do we multiply it with to get a whole number?

A

5

353
Q

What’s an alternative method for calculating concentrations?

A
  1. Work out the amount of moles in 1dm^3 of the solution
  2. Multiply this by the mor ratio value

For example…
As203 + 3H20 —> 2H3As03
n = m. 0.0104 moles in 100cm^3 of As203
—
M

So, in 1dm^3 —> 0.0104 x 10 = 0.104mol
Concentration of H3As03 —> 0.104 x 2 = 0.208moldm^3

354
Q

Why doesn’t it matter if some solid remains in a weighing bottle?

A

We’re weighing by difference

355
Q

Do you use mass or moles to calculate percentage yield?

A

Either is fine

356
Q

How do we calculate the mass of a certain element present in a sample?

A

Total mass x Mr element
——————
Mr total

357
Q

What is the error in a mass when weighing by difference?

A

+-0.0005g

358
Q

Which impurities are removed from a sample when washed?

A

Soluble impurities

359
Q

How do we know what our error is to use when calculating percentage error?

A

Half the unit of the last decimal place

360
Q

What’s the uncertainty of our measurement when using a 2 d.p balance?

A

+-0.005

361
Q

If you get 2 different mole values you could use in a % yield question, which one do we use? Why?

A

Figure out which one is lowest - this is the limiting factor
Use this for the theoretical yield

362
Q

What type of ions does the mass spectrometer produce?

A

Positive ones

363
Q

Under what condition is the whole system of a mass spectrometer?

A

Under vacuum

364
Q

What’s a different way in which a percentage yield question could be asked?

A

Percentage purity

365
Q

Why is the entire inside of a mass spectrometer under vacuum?

A

So that air molecules don’t interfere with the movement of the ions

366
Q

How many dm^3 in a litre?

A

1

367
Q

How do we go from gdm^-3 to moldm^-3?

A

Divide by Mr

368
Q

Error in a 2 decimal place balance

A

+-0.005g

369
Q

Relationship between cm^3 and grams?

A

(Under the correct conditions…)
1cm^3 = 1g

370
Q

Do we use molar ratio (big numbers) in percentage by mass questions?

A

No

371
Q

What do we input as our “error” with percentage errors?

A

Half the tolerance of the equipment

Chemistry (39 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions