Energy Transfers 3.5 Flashcards

Question 1

Q

Photosynthesis (AO1)

Which reaction comes first in photosynthesis?

Answer

A

Light-dependent

Question 2

Q

Photosynthesis (AO1)

During photosynthesis, plants produce ____________ compounds which contain carbon, such as carbohydrates, lipids and proteins.

Question 3

Q

Photosynthesis (AO1)

Most of the sugars synthesised by plants during photosynthesis are used by the plant in ____________ .
The rest are used to make other groups of biological molecules.

Answer

A

respiration

Question 4

Q

Photosynthesis (AO1)

Chlorophyll location

Answer

A

Thylakoid membrane
(found in chloroplasts).

Question 5

Q

Photosynthesis (AO1)

What process do photoautotrophic organisms use to convert carbon dioxide into organic molecules?

Answer

A

Photosynthesis

Question 6

Q

Photosynthesis (AO1)

Examples of photoautotrophic organisms

Answer

A

plants

algae

Question 7

Q

Photosynthesis (AO1)

Light-dependent reaction location

Answer

A

Thylakoid membrane
(found in chloroplasts).

Question 8

Q

Photosynthesis (AO1)

What molecule’s electrons are excited / released during photoionisation?

Answer

A

Chlorophyll

Question 9

Q

Photosynthesis (AO1)

TRUE or FALSE:
Chlorophyll absorbs all wavelengths of light

Answer

A

FALSE

The pigment ‘chlorophyll a’ does NOT absorb green light, so reflects it

Question 10

Q

Photosynthesis (AO1)

What is the term for the splitting of water by light energy into protons, electrons and oxygen?

Answer

A

Photolysis

Question 11

Q

Photosynthesis (AO1)

Which chemicals are needed for the light-dependent reaction

Answer

A

NADP, ADP, Pi and water

Question 12

Q

Photosynthesis (AO1)

Describe photoionisation
(2 marks).

Answer

A

1. Chlorophyll absorbs light energy

OR light energy excites / releases electrons from chlorophyll;

2. Electron/s go to the electron transport chain

Question 13

Q

Photosynthesis (AO1)

Molecules located in the thylakoid membranes

Answer

A

Chlorophyll

Electron transport chain proteins
(includes channel protein for protons)

ATP Synthase
(includes channel protein for protons)

Question 14

Q

Photosynthesis (AO1)

Products of the light-dependent reaction

Answer

A

NADPH and ATP

Reduced NADP is accepted.

Question 15

Q

Photosynthesis (AO1)

Describe what happens during the light-dependent reaction (5 marks).

Answer

A

Chlorophyll absorbs light energy;
Excites electrons / electrons removed (from chlorophyll);
Electrons move along electron transport chain releasing energy;
Energy used to join ADP and Pi to form ATP;
Photolysis of water produces protons, electrons and oxygen;
NADP reduced by electrons and protons

Question 16

Q

Photosynthesis (AO1)

______________ enters most ecosystems through the light-dependent reaction of photosynthesis.

Question 17

Q

Photosynthesis (AO1)

Describe the role of chlorophyll in photolysis (3 marks).

Answer

A

Absorbs light energy;

Loses electrons;

Accepts electrons from water;

Question 18

Q

Photosynthesis (AO1)

Describe how NADP is reduced in the light-dependent reaction of photosynthesis (2 marks).

Answer

A

by electrons and protons from photolysis;

by electrons from chlorophyll;

Question 19

Q

Photosynthesis (AO1)

What molecule is a nitrogen-containing biological molecule, a type of nucleotide, and has two phosphate groups?

Answer

A

NADP

This is useful knowledge for the essay!

Question 20

Q

Photosynthesis (AO1)

What process involves the movement of protons down an electrochemical gradient to produce ATP?

Answer

A

Chemiosmosis

Question 21

Q

Photosynthesis (AO1)

The light independent reaction is also known as the __________ cycle

Question 22

Q

Photosynthesis (AO1)

Light independent reaction location

Question 23

Q

Photosynthesis (AO1)

Rubisco location

Question 24

Q

Photosynthesis (AO1)

Describe the function of NADPH in the light-independent reaction.

Answer

A

Provides H / electrons for the reduction of GP to triose phosphate

Question 25

Q

Photosynthesis (AO1)

Describe the function of ATP in the light-independent reaction (1 mark).

Answer

A

Provides energy for the reduction of GP to triose phosphate;

Provides Pi / inroganic phosphate to convert triose phosphate to RuBP;

Question 26

Q

Photosynthesis (AO1)

Describe the light-independent reaction of photosynthesis (6 marks).

Answer

A

Carbon dioxide combines/reacts with ribulose bisphosphate/RuBP;
Produces two GP molecules using (enzyme) Rubisco;
GP reduced to triose phosphate;
Using reduced NADP / NADPH;
Using energy from ATP hydrolysis;
Triose phosphate converted to glucose / RuBP / named organic substance;

Question 27

Q

Photosynthesis (AO1)

Describe how the products of the light-dependent reaction are used in the light-independent reaction to produce triose phosphate (3 marks).

Answer

A

ATP and reduced NADP / NADPH;
GP reduced to triose phosphate;
ATP provides energy;

Question 28

Q

Photosynthesis (AO3)

Environmental factors that should be controlled when measuring the rate of photosynthesis

Answer

A

Light intensity
Carbon dioxide concentration
Temperature
Water OR humidity
Wavelength of light

Note: which factors are controlled depends on the IV of the experiment

Question 29

Q

Photosynthesis (AO1)

Limiting factors for photosynthesis

Answer

A

Temperature
Carbon dioxide concentration
Light intensity
Wavelength of light

Question 30

Q

Photosynthesis (AO3)

Explain why scientists measured the rate of production of oxygen when investigating the rate of photosynthesis (2 marks).

Answer

A

Oxygen is produced in the light dependent reaction;

The faster the oxygen produced, the faster the light dependent reaction;

Question 31

Q

Photosynthesis (AO2)

Heat stress is a condition that often occurs in plants exposed to high temperatures for a prolonged period of time. Heat stress is a major factor in limiting the rate of photosynthesis.

Heat stress decreases the light-dependent reaction of photosynthesis.

Explain why this leads to a decrease in the light-independent reaction (2 marks).

Answer

A

Less ATP;
Less reduced NADP / NADPH;

Question 32

Q

Photosynthesis (AO2)

Atrazine is a herbicide used to reduce the growth of weeds.

Atrazine binds to proteins in the electron transfer chain in chloroplasts of weeds, reducing the transfer of electrons down the chain.

Explain how this reduces the rate of photosynthesis in weeds (4 marks).

Answer

A

Reduced transfer of protons across thylakoid membrane

OR

Reduced chemiosomotic gradient / proton gradient across thylakoid membrane;

(So) less ATP produced;
(So) less reduced NADP / NADPH produced;
(So) less reduction of GP to triose phosphate.

OR

(So) light-independent reaction slows / stops;

Question 33

Q

Photosynthesis (AO2)

Iron deficiency reduces electron transport. Use this information and your knowledge of photosynthesis to explain the decrease in production of triose phosphate in the iron-deficient plants (4 marks).

Answer

A

ATP and reduced NADP produced during light-dependent reaction;

(In the case of iron deficiency)

Less ATP produced;
Less reduced NADP produced;
Less GP to triose phosphate;

Question 34

Q

Photosynthesis (AO2)

Some bacteria use hydrogen sulfide, H2S, to produce organic compounds. The hydrogen sulfide has a similar role to that of water in photosynthesis.

A simple equation for this process in bacteria is shown below:

hydrogen sulfide + carbon dioxide → glucose + sulfur + water

Suggest what the hydrogen sulfide is used for in these bacteria (2 marks).

Answer

A

(Provides) hydrogen/protons/H+ and electrons/e-;
For reduction (of NADP);
Source of electrons for chlorophyll / electron transfer chain;

Question 35

Q

Photosynthesis (AO2)

Another effect of heat stress is a decrease in the activity of the enzyme rubisco. A decrease in the activity of an enzyme means that the rate of the reaction it catalyses becomes slower.

A decrease in the activity of the enzyme rubisco would limit the rate of photosynthesis.

Explain why (2 marks).

Answer

A

Less carbon dioxide (reacts) with RuBP;
Less GP;

Question 36

Q

Photosynthesis (AO2)

An investigation was carried out into the effect of carbon dioxide concentration and light intensity on the rate of photosynthesis in a species of plant.

The temperature was kept constant during this investigation. Explain why (2 marks).

Answer

A

Temperature affects photosynthesis;

because it affects enzyme activity;

So that any change in photosynthesis rate is result of carbon dioxide / light intensity;

Question 37

Q

Photosynthesis (AO2)

Data from an investigation showed that mutant plants producing more chlorophyll b grow faster than normal plants in all light intensities.

Explain how (4 marks).

Answer

A

Have faster production of ATP and reduced NADP;
(So) have faster / more light-independent reaction;
(So) produce more sugars that can be used in respiration;
(So) have more energy for growth;
Have faster / more synthesis of new organic materials (e.g. amino acids).

Question 38

Q

Respiration (AO1)

Respiration produces ………………………

Question 39

Q

Respiration (AO1)

Aerobic respiration stages

Answer

A

1. Glycolysis
2. Link reaction
3. Krebs cycle
4. Oxidative phosphorylation

Question 40

Q

Respiration (AO1)

TRUE OR FALSE:

Glycolysis is the first stage of anaerobic AND aerobic respiration

Question 41

Q

Respiration (AO1)

Glycolysis location

Answer

A

Cytoplasm

Question 42

Q

Respiration (AO1)

Describe glycolysis (4 marks)

Answer

A

1. Phosphorylation of glucose using ATP;

2. Oxidation of triose phosphate to pyruvate;

3. Net gain of (2) ATP (molecules);

4. NAD reduced/ NADH produced;

Question 43

Q

Respiration (AO1)

Dehyrogenase action during glycolysis

Answer

A

Removes hydrogen from triose phosphate so oxidised to pyruvate

Adds hydrogen to NAD so reduced to NADH

Question 44

Q

Respiration (AO1)

During glycolysis, ATP is produced via ____________-____________ phosphorylation

Answer

A

substrate-level

Question 45

Q

Respiration (AO1)

Net yield of 2 ATP during glycolysis

Answer

A

2 ATP used to phosophorylate glucose

4 ATP produced during substrate level phosphorylation (triose phosphate to pyruvate)

Question 46

Q

Respiration (AO1)

TRUE or FALSE:
Anaerobic respiration produces more ATP than aerobic respiration

Answer

A

False

Lots of ATP is produced during oxidative phosphorylation

Question 47

Q

Respiration (AO1)

If respiration is aerobic, pyruvate from glycolysis enters the mitochondrial matrix by…………………….

Answer

A

active transport

Question 48

Q

Respiration (AO1)

TRUE or FALSE:
Glucose crosses the double membrane of mitochondria via active transport

Question 49

Q

Respiration (AO1)

Link reaction location

Answer

A

(Mitochondrial) matrix

Question 50

Q

Respiration (AO1)

Fill in the blanks:

During the first step of the link reaction pyruvate is oxidised to [1] and the removed hydrogen is used to reduce [2]. During this step, carbon [3] is also released/removed by the enzyme [4].

Answer

A

acetate
NAD
dioxide
decarboxylase

Question 51

Q

Respiration (AO1)

Carbons in pyruvate

Answer

A

3 carbons

Question 52

Q

Respiration (AO1)

Carbons in acetate

Answer

A

2 carbons

Question 53

Q

Respiration (AO1)

Answer

A

A - pyruvate

B - reduced NAD / NADH

C - coenzyme A

D - AcetylcoenzymeA

Question 54

Q

Respiration (AO1)

Decarboxylase action during link reaction

Answer

A

removes carbon during oxidation of pyruvate, releasing carbon dioxide and resulting in the formation of acetate

Question 55

Q

Respiration (AO1)

Describe how acetylcoenzyme A is formed in the link reaction (2 marks)

Answer

A

1. Oxidation of / hydrogen removed from pyruvate AND carbon dioxide released;

2. Addition of coenzyme A (to 2C acetate).

Question 56

Q

Respiration (AO1)

Link reaction reactants

Answer

A

Pyruvate
NAD
CoenzymeA

Question 57

Q

Respiration (AO1)

Acetylcoenzyme A reacts with a four-carbon molecule, releasing coenzyme A and producing a six-carbon molecule that enters the ……………………..

Answer

A

Krebs cycle

Question 58

Q

Respiration (AO1)

Krebs cycle location

Answer

A

(Mitochondrial) matrix

Question 59

Q

Respiration (AO1)

The Krebs cycle is a series of oxidation-reduction reaction that produces………

Answer

A

Products through oxidation-reduction:

Reduced NAD / NADH
Reduced FAD / FADH

other products:

ATP by substrate-level phosphorylation
Carbon dioxide
A 4C molecule

Question 60

Q

Respiration (AO1)

Importance of the 4C product from the Krebs cycle

Answer

A

Allows the Krebs cycle to continue;

So more NADH and FADH produced;

So more ATP can be produced during oxidative phosphorylation

Question 61

Q

Respiration (AO1)

Enzyme that produces NADH and FADH

Answer

A

Dehydrogenase

Question 62

Q

Respiration (AO1)

Enzyme that produces carbon dioxide during the link reaction and Krebs cycle

Answer

A

Decarboxylase

Question 63

Q

Respiration (AO1)

TRUE OR FALSE:

FADH is produced during the link reaction and Krebs cycle

Answer

A

FALSE

FADH is only produced during the Krebs cycle

Question 64

Q

Respiration (AO1)

Draw out the Krebs cycle

Answer 56

A

1. Less/no reduced NAD/ reduced FAD

2. Oxygen is the final/terminal (electron) acceptor;

Less NADH/FADH = less electron transfer, so less oxygen required.

Answer 57

A

(High energy) electrons

Answer 58

A

In the cristae (the folds of the inner mitochondrial membrane)

Answer 59

A

Large surface area, so more inner membrane to embed more electron transport chain (e.g. proton pumps) and ATP synthase.

Answer 60

A

Substrate level phosphorylation

ATP produced in Krebs cycle;

Oxidative phosphorylation

Krebs cycle and link reaction produces NADH;

OR Krebs cycle produces FADH;

Electrons released from NADH / FADH;
(Electrons) pass along carriers / through electron transport chain / through series of redox reactions;
Energy released;
Protons move into intermembrane space (electrochemical / proton gradient forms);

(Protons move down electrochemical gradient and release energy used to combine)

ADP + Pi;
ATP synthase

Answer 61

A

1. ATP formed as electrons pass along transport chain (ETC);

2. Oxygen is final electron acceptor / accepts electrons from electron transport chain;

3. Forms H2O;

4.. Electrons cannot be passed along electron transport chain if there is no O2 to accept them;

Answer 62

A

1. Removal of hydrogen;

2. By enzymes/dehydrogenases;

3. H accepted by NAD / reduced NAD formed;

(Triose phosphate is oxidised)

4. In Krebs cycle, FAD (used as well);

Answer 63

A

Fatty acids

Glycerol

Amino acids

Answer 64

A

Less / no malonyl-CoA produced;
More fatty acids transported / moved into mitochondria;
Respiration / oxidation of fatty acids provides ATP;

Answer 65

A

Yeast
Bacteria
Some plants

Answer 66

A

Muscle cells

Specifically fast-twich muscle fibres e.g. for sprinting

Answer 67

A

Lactate / lactic acid

ATP (net yield of 2 ATP)

NAD

Answer 68

A

Glycolysis
Regeneration of NAD

Answer 69

A

Cytoplasm

Answer 70

A

Reduction of pyruvate

Answer 71

A

Regenerates NAD
(accept oxidises reduced NAD);
NAD used in glycolysis.

Answer 72

A

Pyruvate used in aerobic respiration / can enter the link reaction

OR

Less lactate so less cramp / muscle fatigue.

Answer 73

A

ATP cannot be stored / is an immediate source of energy;
ATP only releases a small amounts / packets of energy at a time;

Answer 74

A

Oxygen is final/terminal (electron) acceptor /
(This allows aerobic respiration) oxidative phosphorylation / electron transfer chain;
Anaerobic (respiration) only glycolysis occurs
(so some ATP produced via substrate level phosphorylation)

Answer 75

A

Fewer cristae/smaller surface area (of cristae);
So less electron transport/oxidative phosphorylation;
(So) not enough ATP produced

OR Not enough energy to keep neurones alive;

Answer 76

A

toxic

This may lead to some yeast cells dying

Answer 77

A

respirometer

Answer 78

A

Insects
Seeds
Yeast
Other mircoorganisms e.g., bacteria

Respirometer is suited for small organisms only

Answer 79

A

FALSE

Can be adapted to measure anaerobic respiration

Answer 80

A

1. Oxygen used by seeds (aerobic respiration);

2. Carbon dioxide produced is absorbed by potassium hydroxide;

3. Decrease in pressure/volume (of air inside);

Answer 81

A

1. Distance liquid moves;

2. Diameter/radius of the tubing/lumen

Answer 82

A

1. Equilibrium reached / allow to equilibrate

2. Allow for pressure change in apparatus;

3. Allow respiration rate of seeds to stabilise.

Answer 83

A

Prevents oxygen being taken up / entering / being absorbed

Answer 84

A

Affects enzymes;
Affects respiration;

OR

Affects volume / pressure of gases;
Affects readings;

Answer 85

A

1. Decrease/no glucose/substrate;

(Switch from aerobic to anerobic respiration)

2. Increase in ethanol/carbon dioxide/acidity;

Answer 86

A

organic

Organic means the molecule contains c-c or c-h bonds

Answer 87

A

photosynthetic

Answer 88

A

producers

Answer 89

A

Saprobionts / decomposers

Answer 90

A

1. Light being reflected

2. Pigments may not absorb the wavelength of light received

3. Light may miss the chlorophyll

4. There is another limiting factor that means that the light cannot be used e.g. carbon dioxide concentration

Answer 91

A

1. Energy lost during transfer between trophic levels;

(Humans eating cattled adds a trophic level)

2. Energy lost via respiration / heat loss / maintaining temperature / muscle contraction / movement

Also accept: excretion / faeces / parts of food not eaten e.g. roots/bones;

Answer 92

A

1. Heat loss from respiration;

2. Food not digested / not all eaten OR faeces;

3. Excretion OR urine;

Answer 93

A

Total mass of carbon per given area per given time

OR

Total dry mass of tissue per given area per given time

Answer 94

A

calorimetry

Answer 95

A

1. Heat at 100°C to evaporate water;

2. Weigh and heat until no further change in mass

Answer 96

A

1. Water content present will vary in fresh mass;

2. This issue will not affect dry mass;

Answer 97

A

photosynthesis

Answer 98

A

NPP = GPP-R
Where:
GPP = Gross primary production
R = respiratory losses

Answer 99

A

plant growth and reproduction;

contains energy that can passed onto the next trophic level;

Answer 100

A

N = I - (F+R)

Answer 101

A

I = Chemical energy/store of ingested/consumed food

Answer 102

A

(energy loses due to)

F = faeces AND urine

Answer 103

A

R = Respiratory losses

(due to heat loss / maintaining temperature / movement)

Answer 104

A

N = net production of consumers

Answer 105

A

Sample of (dry) biomass is combusted;

This releases heat energy;

This warms the surrounding water;

The larger the temperature increases of water, the more energy stored in the biomass;

Water is used because it has a high specific heat capacity
(we know much energy is required to heat 1cm3 of water by 1oC).

Answer 106

A

Stirrer distributes heat energy;
Insulation by air spaces reduces heat loss
Water has a high specific heat capacity

Answer 107

A

Respiration / heat loss / maintaining body temperature / movement;

Answer 108

A

Organic
Respiration
Carbon

Accept tissue(s)/plant(s)/animal(s)/organism(s)

Calorimetry;

Answer 109

A

1. Low respiration;

Accept less energy lost in respiration

2. More growth/biomass

Answer 110

A

More energy is available for growth/biomass

Answer 111

A

1. Insecticides/pesticides/fungicides are used to exclude competitors who may feed on crops;

2. This means a higher N (net production of consumers) / more energy available for growth/biomass of crops

Answer 112

A

Nitrogen fixation
Nitrification
Ammonification
Denitrification

Answer 113

A

Nitrogen fixing bacteria

Answer 114

A

Root nodules

OR

Free in the soil

Answer 115

A

Convert atmospheric nitrogen
into ammonia

Answer 116

A

Ammonia into nitrites;
Nitrites into nitrates;
By nitrifying bacteria

Answer 117

A

Denitrifying bacteria

Answer 118

A

Convert nitrates in the soil into atmospheric nitrogen

Answer 119

A

Anerobic / waterlogged soil

Answer 120

A

assimilated

Answer 121

A

Saprobionts

Answer 122

A

1. (use enzymes to decompose) proteins / DNA / RNA / urea;

2. Producing ammonia / ammonium ions;

Answer 123

A

(Nitrogen fixation)
1. Nitrogen into ammonia;
2. By nitrogen-fixing bacteria;

(Nitrification)
3. (oxidation of) ammonia into nitrite;
4. Nitrite into nitrate;
5. By nitrifying bacteria;

(Ammonification)
6. protein / amino acids / DNA into ammonia
7. (use enzymes to decompose) by saprobionts;

Answer 124

A

Any two from:
1. amino acid / protein / polypeptide / peptide;

nucleic acid / nucleotide / base;
DNA;
RNA;
ATP / ADP;
NAD / NADP (reduced or not);
Cyclic AMP / cAMP;
Chlorophyll;

Answer 125

A

(Ammonification)
1. Protein/amino acids/DNA/urea into ammonia;
2. By saprobionts

(Nitrification)
3. Ammonia into nitrite;
4. Nitrite into nitrate ;
5. By nitrifying bacteria;

Note: there are no marks for the role of nitrogen-fixing bacteria as the question refers to producing a source of nitrates from the remains of crops.

Answer 126

A

1. (Fertility increased as) less nitrate removed;

Accept: Nitrate remains

2. Less denitrification / fewer denitrifying bacteria.

Accept: more nitrification / more nitrifying bacteria / process R is increased

Answer 127

A

Add natural (e.g. manure / compost) AND/OR
artificial (e.g. liquid ammonia) fertilisers

Answer 128

A

1. Less nitrification

OR Fewer/less active nitrifying bacteria;

OR Nitrifying bacteria require oxygen/aerobic conditions;

2. (Less) oxidation/conversion of ammonia to nitrite (ions) and to nitrate (ions);

3. More denitrification

OR More/more active denitrifying bacteria

OR denitrifying bacteria require anaerobic conditions;

(So more) nitrate (ions) reduced/converted to nitrogen (gas);

Answer 129

A

Mycorrhizae

Answer 130

A

Increase uptake of water and inorganic / mineral ions (e.g. phosphate and nitrate) by plants

Answer 131

A

Increase surface area;

For absorption of water and inorganic / mineral ions;

Which are used for growth / protein synthesis / respiration / photosynthesis

Answer 132

A

Receive a carbon-containing biological molecule e.g. glucose / carbohydrate / amino acid;

Answer 133

A

Used to produce named phosphate compound in cells;

e.g. ATP / ADP / phospholipids / DNA / RNA / RuBP / Triose Phosphate /GP.

Answer 134

A

1. Less/no ATP/energy required/used

OR More ATP/energy available;

2. ATP/energy can be used for growth/synthesis/replication

OR Lower (rate of) respiration required

OR ATP for phosphorylation;

Answer 135

A

1. Grow crops / plants with nitrogen-fixing (bacteria);

Accept: grow legumes / named example e.g. peas, beans, clover

Accept: fallow year

2. (Different crops use) different minerals / salts / nutrients / ions (from the soil);

3. (Different crops have) different pests / pathogens / diseases.

Answer 136

A

Phosphate ions in rocks are eroded by water/weather
Dissolve into water systems and soil
Absorbed by plants and assimilated into compounds such as nucleic acids and phospholipids
These can be passed on during feeding to higher trophic levels
Excretion of phosphate ions in waste and decomposition of remains by saprobionts
Deposition of these phosphate ions leads to phosphate held in rocks

OR

Sedimentation of phosphate ions in water leads to phosphates in rocks

Answer 137

A

P = Nitrification

Q = Denitrification

Answer 138

A

Nitrification

Answer 139

A

Increase concentration of nitrate and phosphate in freshwater;

Leds to algal growth / algal bloom which block light

Answer 140

A

Saprobionts decompose dead plant material;

Aerobically respire / use oxygen in respiration;

Less oxygen for fish to aerobically respire so they die;

Answer 141

A

(Eutrophication)
1. Growth of algae / surface plants / algal bloom blocks light;

Reduced / no photosynthesis so submerged plants die;
Saprobiont;
Aerobically respire / use oxygen in respiration;
Less oxygen for fish to respire / aerobic organisms die;

Answer 142

A

1. Use of colorimeter;

2. Measure the absorbance/transmission (of light);

3. Example of how method can be standardised eg same volume of water, zeroing colorimeter, same wavelength of light, shaking the sample;

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Energy Transfers 3.5 Flashcards

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