Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Chemistry > Chem test 9th grade > Flashcards

Chem test 9th grade Flashcards

(60 cards)

Start Studying
1
Q

What is atomic mass

A

It is how many grams in a mole

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

How much is one mole

A

a collection of 6.02 x 10^23 things

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

Is a mole a molecule

A

no

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

Who discovered moles

A

Avogadro

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

what is a molecule

A

It is a combo of two or more atoms held together by chemical bonds

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

What do subscripts tell you

A

how many of each atom there are in one molecule

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

how do you go from number of particles to number of moles

A

divide by avogadros number

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

What is avogadros number

A

6.02 x 10^23

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

how do you go from number of moles to mass

A

multiply by molar mass

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

how do you go from mass to number of moles

A

divide by molar mass

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

how do you go from number of moles to number of particles

A

multiply by avogadros number

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

moles to litres

A

do moles x 22.4

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

litres to moles

A

litres / 22.4

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

1 mole of gas =

A

22.4 litres

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

molar mass number =

A

atomic mass number

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

to balance equations, you must

A

add coefficients to make all elements equal on either side

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

what are ions

A

atoms with a positive or negative charge due to the loss/gain of electrons

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

what is an covalent bond

A

elements that share electrons

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

What is an ionic bond

A

when elements lose/gain an electron

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

What is electronegativity

A

how strong an atom is (can it steal your electrons) The measure of an atom’s ability to attract electrons to itself

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

What is the strongest and weakest electronegativity

A

4 is strongest, 1 is weakest

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

Why do covalent bonds occur

A

Because the two elements are too similar in electronegativity and therefore can’t steal so therefore share

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

what is relative atomic mass?

A

the average atomic mass of all the naturally occurring isotopes of a given element

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

How is atomic mass measured

A

in Amu which is 1/12 the mass of carbon 12

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
How many atoms are there in 12 grams of carbon 12?
there are 6.02 x 10^23 atoms
26
To find the molar mass of a compound do
multiply the subscript by the atomic mass of all the elements then add together all the numbers
27
How is energy increased
temperature
28
What conditions are needed for a reaction to occur
minimum kinetic energy collide with each other be facing the correct way when they collide
29
What does higher concentration do
when theres higher concentration, there are more particles to collide meaning more collisions. greater chance of successful collisions results in more product made in the same time
30
What does collision theory state
that for a reaction to occur, the particles involved must collide with the correct orientation and sufficient energy
31
Higher surface area means
more room for reaction to occur. The larger the surface area, the faster the reaction occures
32
What element are humans primarily made from
carbon
33
what happens after two half lives and after three?
after one you get 1/2, after two you get 1/4, after three you get 1/8 and so on
34
What does endo stand for
inside (cold
35
What does exo stand for
outside (hot)
36
What does thermic stand for
heat
37
What is activation energy
the minimum amount of energy colliding particles need for a collision to be successful and for a reaction to occur
38
what is an exothermic reaction
a chemical reaction during which heat is released into surroundings
39
What is an endothermic reaction
a chemical reaction during which heat is absorbed form the surroundings
40
What does an exothermic graph look like
It is flat where the reactants are there is a curve up then down then the products are flat below where the reactants where
41
What does an endothermic graph look like
reactants are flat line curve up to products products are flat line above reactants x axis is reaction progress y axis is potential energy
42
What is a catalyst
a substance that increases the rate of a chemical reaction without itself undergoing any permanent change, by lowering the activation energy
43
what is the rate of chemical reactions
speed at which reactants turn into products
44
how do you calculate the average rate of reactants
either change in mass of reactants used / time taken change in mass of products used / time taken answer is in cm^3 per second *time is always seconds*
45
what does a graph look like when you use quantity of reactants
y axis is mass of reactants x axis is time line curving down in a slide
46
What does a graph look like when you use the volume of product
y axis is volume of products x axis is time line curves upward in a rainbow
47
What are factors that affect rate of a chemical reaction
temperature surface area concentration/pressure catalyst
48
If particles don't have enough energy then...
nothing happens
49
Rate also depends on
frequency of collisions amount of energy particles have
50
How does temp affect rate of chemical reaction
particles gain more energy which causes them to move faster, and collide with more energy
51
How does pressure/concentration affect rate of chemical reaction
as pressure/concentration increases, there are more particles per unit of volume, making collisions more frequent
52
How does surface area affect rate of chemical reaction
higher surface ares means more area for collisions to occur which means frequency of collisions would be higher
53
How does a catalyst affect rate of chemical reaction
catalysts lower activation energy creating a higher proportion of successful collisions
54
When are reactions the fasted?
At the beginning, then they slow down until they stop
55
How do you tell if one reaction is faster than the other
Whichever line is steeper is the faster reaction
56
how to determine percentage yield
(actual yield / theoretical yield)100
57
how to find actual yield
(percentage x theoretical)100
58
Why does percent yield exist
1. reactants might not all react or begins to reverse - slow reaction and not all reacts 2. side reactions 3. some is lost during the process - spilled - left in the container
59
relative vs molar mass
relative - mass of a single molecule molar mass - mass of a mole
60
triangles
grams / moles x molar mass particles / moles x 6.02 x 10^23

Chemistry (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions