Module 8: Applying Chemical Ideas Flashcards
(137 cards)
1
Q
What is the water cycle?
A
Evaporation, transpiration, condensation, precipitation, flow and run offs
2
Q
What are pollutants?
A
Substances that have a negative impact on the environment
3
Q
What impact does phosphate have on the environment?
A
Introduced via fertilisers they can cause algae blooms depleting water of O2
4
Q
What impact does ozone have on the environment?
A
In lower levels it can damage vegetation and cause health issues
5
Q
What is the Murray-Darling Basin?
A
A basin which covers 14% of Australia and accounts for 40% of Australia’s agricultural production
6
Q
What are some environmental issues with the Murray-Darling Basin?
A
Salinity, erosion, blue green algae and water quality
7
Q
What does chemical analysis do?
A
Provides safe drinking water, healthy food, maintain air control and water quality
8
Q
What is qualitative analysis?
A
Is the identification of a substance or components in a mixture
9
Q
What is usually tested during qualitative analysis for water?
A
Domestic water
Irrigation
Food manufacturing and processing
Pathology
10
Q
What is the flame test?
A
A qualitative test identifying a particular cation, metal ion
11
Q
How does the flame test work?
A
Some heated metals produce distinctive coloured flames according to the movement of electrons
12
Q
What are the two methods for the flame test?
A
With solid material on a wire loop placed in the flame or a solution sprayed into the bunsen burner flame
13
Q
Flame test colour of Li?
A
Crimson
14
Q
Flame test colour of Na?
A
Yellow
15
Q
Flame test colour of K?
A
Purple
16
Q
Flame test colour of Ca?
A
Red
17
Q
Flame test colour of Sr?
A
Scarlet
18
Q
Flame test colour of Ba?
A
Yellow-green
19
Q
Flame test colour of Cu?
A
Green
20
Q
Flame test colour of Pb?
A
Pale blue/white
21
Q
Flame test colour of Fe?
A
Yellow-golden
22
Q
What are three limitations of the flame test?
A
Only works on some cations
Is a destructive test
Limited by interference and ambiguities
23
Q
What is a precipitate?
A
A solid that can form when two solutions mix
24
Q
What is the precipitation test?
A
Is a qualitative test that identify ions present in a solution
25
Are group 1A ions soluble?
Yes
26
Is Cl soluble?
Yes except when with Ag or Pb
27
Is Br soluble?
Yes except when with Ag or Pb
28
Is I soluble?
Yes except when with Ag or Pb
29
Is SO4 soluble?
Yes except when with Ba, Pb Sr, Ag and Ca
30
Is CO3 soluble?
No
31
Is PO4 soluble?
No
32
Is S soluble?
No
33
Is OH soluble?
No except when with Ag, Ba, Ca, Sr
34
What colour is the precipitate with Ba?
White
35
What colour is the precipitate with Ca?
White
36
What colour is the precipitate with Pb?
White
37
What precipitates are blue?
Cu(OH)2, Cu3(PO4)2
38
What precipitates are green?
CuCO3, Fe(OH)2, Fe3(PO4)2
39
What precipitates are grey?
FeCO3
40
What precipitates are brown?
Fe(OH)3
41
What precipitates are yellow?
AgOH, Ag3PO4, Ag2CO3
42
What colour precipitate is AgCl?
White
43
What colour precipitate is Ag2SO4?
White
44
What does NAG SAG stand for and what does it mean?
Things that are nearly always soluble
Nitrate
Ammonium
Group one
Sulfates
Acetate
Group 17
45
What does PMS Casrba stand for?
Lead
Mercury
Silver
Calcium
Strontium
Barium
46
What does the PMS mean in the acronym?
Insoluble with sulfates and and group 17
47
What does casrba mean in the acronym?
Insoluble with sulfates
48
What is the first thing you should add to unknown liquid when testing for metals?
NaCl
49
What does it mean if a white PPT forms when NaCl is added?
It has Pb or Ag
50
What is the second thing you should add to unknown liquid when testing for metals?
Na2SO4
51
What does it mean if a white PPT forms when Na2SO4 is added?
It has Ba or Ca
52
What is the third thing you should add to unknown liquid when testing for metals?
NaOH
53
What does it mean if a white PPT forms when NaOH is added?
It has Mg
54
What does it mean if a blue PPT forms when NaOH is added?
It has Cu
55
What does it mean if a green PPT forms when NaOH is added?
It has Fe2+
56
What does it mean if a brown PPT forms when NaOH is added?
It has Fe3+
57
What is the first thing that should be added when testing for anion?
HNO3
58
What does it mean if bubbles form when HNO3 is added?
It has CO3
59
What is the second thing that should be added when testing for anion?
Red litmus paper
60
What does it mean if the red litmus paper turns blue when testing for anions?
It has OH
61
What is the third thing that should be added when testing for anion?
Ba(NO3)2
62
What does it mean if white PPT forms when Ba(NO3)2 is added?
It has SO4
63
What is the fourth thing that should be added when testing for anion?
NH3
64
What does it mean if white PPT forms when NH3 is added?
It has PO4
65
What is the fifth thing that should be added when testing for anion?
PbNO3
66
What does it mean if a yellow PPT forms when PbNO3 is added?
It has I
67
What is the sixth thing that should be added when testing for anion?
AgNO3
68
What does it mean if white PPT forms when AgNO3 is added?
It has Cl
69
What does it mean if cream PPT forms when AgNO3 is added?
It has Br
70
What is gravimetric analysis?
When a precipitate is formed, filtered and then weighed
71
What are the advantages of gravimetric analysis?
Simple and inexpensive and can be used for a range of substances
72
What is a limitation of gravimetric analysis?
Not suitable for soluble salts
73
How do you draw a conductivity titration?
Draw two lines of best fit and where they intersect is equivalence point
74
What is spectroscopy?
Analytical technique that uses visible light and electromagnetic spectrum
75
How does spectroscopy and colorimetry work?
Measure the absorbance of light
76
How do you pick the colour filter for colorimetry?
Colour filter is complementary to the colour of the solution
77
How can you remember the complementary colours?
ROYGBV
VBGYOR
78
How do you make a calibration curve?
Measure absorbance of 5 solutions with different known concentrations and plot it on a graph
79
What are the advantages of colorimetry?
It is inexpensive and easy to carry and transport
80
What are the disadvantages of colorimetry?
It cannot detect colourless compounds and does not work in IR and UV region
81
How is UV-Visible Spectroscopy different to colorimetry?
It uses a monochromator for an exact wavelength rather than a colour filter
82
How is the wavelength selected for spectroscopy?
By testing varying wavelength and seeing which one absorbs the most
83
What is an advantage of spectroscopy?
It is more effective than colorimetry
84
What is the beer lambert law?
It is a mathematical relationship between light absorbed and factors that affect absorbance of light
85
What factors affect the absorbance of light?
The substance, concentration and length of sample cell
86
What do the symbols mean in the beer lambert law equation?
E: molar coefficient in cm molL-1
L: Sample cell length in cm
c: molar concentration molL-1
I0: intensity of light in
I: intensity of light out
87
What is atomic absorption spectroscopy?
Analytical technique measuring concentration of gas phase metal atoms
88
What is the process for AAS?
1. Solution is drawn into a nebuliser and turns into a mist
2. Mist is atomised in the furnace
3. Hallow cathode lamp shine on gaseous atoms
4. Fraction of the light reaches the monochromator
5. Filtered light reaches photomultiplier detector
89
What are the advantages of AAS?
Simple technique, very sensitive, inexpensive, very fast
90
What are the disadvantages of AAS?
High initial machinery cost, destructive test
91
How do you test for alkene?
When adding bromine water which has a distinct red/brown colour an addition reaction occurs turning it clear
92
What is a crucial factor when testing for alkenes using bromine water?
Keep tests out of sunlight as alkanes will also turn clear when exposed to UV
93
What are three ways you can test for carboxyl?
Blue litmus paper turns red
When carbonate added bubbles form
React with alcohol to form an ester
94
How do you test for hydroxyl?
Add sodium metal and hydrogen gas is produced
95
What is the colour change when primary and secondary alcohols are reacted with KMnO4?
Purple to clear
96
What is the colour change when primary and secondary alcohols are reacted with K2Cr2O7?
Yellow to green
97
How do you distinguish between primary, secondary and tertiary alcohol?
Add ZnCl2/HCl mixture:
Primary - does not react
Secondary - will take a long time to react
Tertiary - will react immediately
98
What are the types of energies of atoms and molecules from lowest to highest energy?
Translational
Rotational
Vibrational
Electronic
99
Why should the fingerprint region be ignored in infrared spectroscopy?
As it is unique for every single compound
100
Where is the fingerprint region on an infrared spectroscopy?
Below 1400cm-1
101
How does a nuclear magnetic resonance work?
Uses low frequency radio waves and alters nuclear spin of various nuclei of atoms
102
What nuclei have spin?
Nuclei with an odd atomic number or an odd mass number
103
What does a peak in a Carbon-13 NMR represent?
Each peak represents a carbon environment
104
What are the steps for interpreting a Carbon-13 NMR?
1. How many signals and how many environments that corresponds to
2. These peaks occur at ... which corresponds with ...
105
What does peak area of each signal mean in a hydrogen-1 NMR?
Is equal to the number of hydrogen atoms in ratio
106
What does signal splitting mean?
Number of lines is one more than number of neighbouring H atoms
107
What does mass spectrometry do?
Allows the determination of the exact chemical structure of a molecule
108
What is the process for mass spectrometry?
1. Sample exposed to high voltage forming ions
2. Ions separated by magnetic field based on mass/charge ratio
3. Number of ions with different m/z are measured
109
What is the molecular ion peak?
Is the peak with the largest m/z
110
What is the base peak?
It is the highest peak produced
111
What is fragmentation in mass spectrometry?
When high energy electrons knock off electrons from the sample molecule
112
What is the general formula for alcohols?
CnH2n+2O
113
What is the general formula for haloalkanes?
CnH2n-1X (X=F, Cl, Br or I)
114
What is the general formula for aldehydes and ketones?
CnH2nO
115
What is the general formula for carboxylic acids and esters?
CnH2nO2
116
What is the general formula for amines?
CnH2n+3N
117
What is the general formula for amides?
CnH2n+1ON
118
How do you find the molecular formula?
1. Find molecular ion peak
2. ion peak = relative atomic mass
3. Find n
4. Sub n into general formula
119
What is the Habour process used for?
Is involved in the production of ammonia
120
What is the Habour process reaction?
Exothermic reversible reaction of the combination of nitrogen gas and hydrogen gas to form ammonia
121
What is ammonia used for?
Fertilisers, cleaning agents and many more
122
Where are the reactants for the Habour process obtained from?
Nitrogen - liquefying air
Hydrogen - steam reacting with hydrocarbons
123
What is the compromise for the Habour process?
Yield of about 30% but by recycling unreacted gases 98% yield
Temp 400C and pressure 250atm
124
How is percentage yield calculated?
actual yield/theoretical yield x 100
125
What does atom economy measure?
The percentage of atoms in the reactants that end up in desired product
126
How do you calculate atom economy?
mass of desired products/mass of all reactants x 100
127
What are economic considerations that should be made for chemical procedures?
Use of the product, storage transport and waste disposal, purity and yield, use of energy and water
128
What are environmental considerations that should be made for chemical procedures?
Waste management and potential harms of any chemicals, negative impact on water and atmosphere
129
What is green chemistry?
A set of principles used as a framework to evaluate environmental impact
130
Why is green chemistry different?
It believes the best approach is to not produce waste in the first place
131
Why doesn't alkenes need UV to react with bromine water?
Due to the high reactivity of C=C
132
Why do alkanes need UV to react with bromine water?
Due to low reactivity of C-C
133
What is an example of how acid/base analytical techniques are used in industry?
During the production of wine they use titration methods to determine the acid content as part of their quality control porcess
134
What are three examples of reasons to monitor the murray darling river?
To monitor pollutants that can harm organisms including humans
To keep corporations accountable
To contain and minimise a problem before it spreads
135
What are the two techniques which can be applied when identifying alkane and alkene?
Add bromine water or add potassium permanganate solution
136
What happens to alkene when permanganate solution is added?
It undergoes an oxidisation reaction and turns from purple to brown
137
What happens when to an alkane when permanganate solution is added?
Nothing the liquid stays puple
