Question 1:-
Topic – B15.3 Sexual reproduction in plants
(a) Fig. 1.1 is a diagram of a wind‑pollinated flower.
(i) State which letter in Fig. 1.1 identifies the part where:
fertilisation occurs ………………….
pollen is produced. ………………….
(ii) Describe two visible pieces of evidence in Fig. 1.1 that show the flower is adapted for wind‑pollination.
(b) Fig. 1.2 is a photomicrograph of pollen from an insect‑pollinated flower
Describe two ways the appearance of pollen from a wind‑pollinated flower is different from the pollen from an insect‑pollinated flower.
(c) Some plants can reproduce asexually and sexually.
(i) State two advantages of sexual reproduction compared to asexual reproduction in plants.
(ii) Suggest a situation where asexual reproduction is more useful to a plant in the wild than sexual reproduction.
(d) Reproduction is one of the characteristics of living organisms.
State two other characteristics of living organisms.
▶️Answer/Explanation
Ans :
1(a)(i) C ;
E ;
1(a)(ii) any two from:
feathery stigma ;
small / no, petals ;
anther hangs outside (the, flower / petals) ;
stigma hangs outside (the, flower / petals) ;
1(b) smooth(er) / not spiky ;
small(er) ;
1(c)(i) any two from:
genetic diversity ;
disease unlikely to wipe out all the plants ;
able to adapt to changes in the environment ;
allows, natural selection / evolution / adaptation ;
1(c)(ii) when the plant becomes isolated (from other plants) / when there is a shortage of pollinators / lack of other plants ;
1(d) any two from:
movement ;
respiration ;
sensitivity ;
growth ;
excretion ;
nutrition ;
/Question 2:-
Topic – C1.1 Solids, liquids and gases
A student heats three substances X, Y and Z in a water‐bath.
Table 2.1 shows the state of the three substances before heating, during heating and after cooling.
(a) Draw one line from substance X and one line from substance Y to show the arrangement of the particles before heating.
(b) Describe the difference in the movement of the particles in a solid and in a liquid.
solid ……………………………………………………………
liquid ………………………………………………………….
(c) Explain how we know that the change to substance X is a physical change and not a chemical change.
(d) Substance Z is the ionic compound sodium chloride, NaCl.
Draw a dot‑and‑cross diagram to show the ionic bonding in sodium chloride.
(e) Fig. 2.1 shows the electrolysis of concentrated aqueous sodium chloride.
Complete the three labels on Fig. 2.1 to show the products made.
▶️Answer/Explanation
Ans :
2(a) 
2(b) (solid) idea that particles are vibrating about fixed positions ;
(liquid) particles, move around / slide over, each other ;
2(c) it is reversible / a chemical change is irreversible ;
no new substance is formed / a chemical change produces a new substance ;
2(d) 
2(e) 
Question 3:-
Topic – P3.1 General properties of waves
Fig. 3.1 shows a sea turtle.
(a) (i) On Fig. 3.1, draw an arrow to show the direction of the weight force acting on the sea turtle.
Label your arrow with the letter W.
(ii) Complete the sentence to describe weight.
Weight is a force caused by the effect of a ………………………………………….. field on a ………………………………………….. .
(b) The sea turtle travels a distance of 1200 km in 20 days.
Calculate the average speed of the sea turtle.
Give your answer in km/ h.
average speed = ………………………………………… km/h
(c) A team of scientists fits a tracker unit to the sea turtle to monitor its location.
The tracker unit sends a signal using radio waves each time the sea turtle moves to the surface of the water.
(i) Radio waves are part of the electromagnetic spectrum.
Complete the sentences to compare radio waves to visible light.
Radio waves have a …………………………………… frequency and a …………………………………… wavelength than visible light.
Radio waves and visible light both travel at ……………………………………m/s in a vacuum.
(ii) The radio waves emitted by the tracker unit have a frequency of 1.5 × 109Hz.
Calculate the wavelength of the radio waves.
wavelength = …………………………………………….. m
(iii) The tracker unit uses a battery with an electromotive force (e.m.f.) of 11V that provides a power output of 22mW.
The battery can transfer a total charge of 24000C before it needs replacing.
Calculate the time for which the battery operates before it needs replacing.
time = …………………………….. s
▶️Answer/Explanation
Ans :
3(a)(i) downwards arrow labelled W ;
3(a)(ii) gravitational AND mass ;
3(b) (t=) 480 (hrs) ;
(v=) d / t OR 1200 / 480 ;
(v=) 2.5 (km / h) ;
3(c)(i) lower AND longer / bigger ;
3 × 108 ;
3(c)(ii) (λ=) v/f OR 3× 108 / 1.5× 109 ;
(λ=) 0.20 (m) ;
3(c)(iii) (P=) 0.022 (W) ;
(I=) P/V OR 0.022/11 OR 0.002 ;
(t=) Q/I OR 24000/0.002 ;
(t=) 1.2 × 107 (s) ;
Question 4:-
Topic – B13.3 Homeostasis
(a) Blood glucose concentration is controlled so that it remains within set limits.
State the name given to this type of control.
(b) Fig. 4.1 shows the blood glucose concentration of a person after they have eaten a meal.
Complete the sentences to describe and explain the changes seen in Fig. 4.1.
Carbohydrates such as starch are broken down by the enzyme ……………………. to form simpler sugars.
These simpler sugars are absorbed into the blood. After 30 minutes, the blood glucose concentration reaches a maximum of ……………………… mmol/dm3 .
The increase in blood glucose concentration is detected and the hormone insulin is released from the ………………………………………… .
Insulin causes glucose to be converted to ………………………………………… .
This is then stored in the ………………………………………… reducing the blood glucose concentration to its previous level.
(c) State the names of two hormones that increase blood glucose concentration.
(d) State the name of the component of blood that transports hormones.
(e) Table 4.1 compares nervous and hormonal control.
Complete Table 4.1.
▶️Answer/Explanation
Ans :
4(a) homeostasis ;
4(b) amylase ;
8.0(mmol per dm3) ;
pancreas ;
glycogen ;
liver/muscles ;
4(c) adrenaline ;
glucagon ;
4(d) plasma ;
4(e) 
Question 5:-
Topic – C9.4 Reactivity series
5 Some students investigate the reaction between marble chips and dilute hydrochloric acid.
They react marble chips of three different sizes, A, B and C, with excess dilute hydrochloric acid.
They use the same mass of marble chips, the same concentration of acid and the same temperature for each experiment.
The students measure the volume of carbon dioxide gas every 30 seconds until the reaction finishes.
Fig. 5.1 shows a graph of their results.
(a) (i) State which marble chips, A, B or C, are the smallest.
(ii) Look at the line for marble chips B.
State when the rate of reaction is the greatest.
Choose your answer from the list.
0 – 30s
30 – 60s
60 – 90s
90 – 120s
answer = ……………………. s
(b) The students did the experiments at 20°C.
State how the rate of reaction will change if they do the experiments again at 40°C.
Explain your answer using ideas about collisions between particles.
(c) Calculate the volume occupied by 1.1g of carbon dioxide gas at room temperature and pressure.
The volume of one mole of any gas is 24dm3 at room temperature and pressure (r.t.p.).
[Ar : C, 12; O, 16]
volume of carbon dioxide gas = ………………………………………….. dm3
(d) Carbon dioxide is a greenhouse gas.
State two problems caused by increased concentrations of greenhouse gases.
▶️Answer/Explanation
Ans :
5(a)(i) A ;
5(a)(ii) 0 –30 s ;
5(b) (reaction will be) faster ;
(because)
Any two from:
molecules have higher kinetic energy / molecules are moving faster ;
more molecules with activation energy ;
frequency of collision (of molecules) is higher / more collisions per second ;
more successful collisions ;
5(c) (Mr of CO2) = 12 + 16 + 16 or 44 ;
(moles of CO2) = 1.1 ÷ 44 = 0.025 ;
(volume of CO2) = 0.025 × 24 = 0.60 dm3 ;
5(d) Any two from:
enhanced greenhouse effect ;
climate change ;
correct consequences e.g. altered weather patterns / colder winters / hotter summers / rising sea levels / melting of ice
caps / species extinction / loss of habitat / changes to migration patterns / flooding / drought / more forest fires etc. ;;
Question 6:-
Topic – P1.7 Pressure
Fig. 6.1 shows an electric pressure‑washer being used to wash a car.
(a) The pressure‑washer pumps water at a high pressure through a small nozzle.
The cross‑sectional area of the nozzle is 5.0 × 10–6m2.
The water leaves the nozzle with a pressure of 9.0 × 106Pa.
Calculate the force exerted by the water as it leaves the nozzle.
force = ……………………………………………… N
(b) The pressure‑washer uses a d.c. motor to pump the water out of the nozzle.
Fig. 6.2 shows a diagram of a simple d.c. motor.
(i) The arrows on Fig. 6.2 show the direction of the current.
Draw an arrow to show the direction of the force acting on the coil at the point labelled X.
(ii) Describe the function of the split‑ring commutator in a simple d.c. motor.
(c) After the car has been washed, droplets of cold water remain on the roof of the car.
After a few minutes, the droplets of water have disappeared.
(i) State the name of the process which causes the droplets of water to disappear.
(ii) Describe the process which causes the droplets of water to disappear in terms of molecules.
▶️Answer/Explanation
Ans :
6(a) (F=) P × A or 9.0 × 106 × 5.0 × 10–6 ;
(F=) 45 (N) ;
6(b)(i) arrow drawn upwards ;
6(b)(ii) provides an alternating current (in the coil) / current that changes direction every half-turn / to reverse the current every half turn/180° ;
allows coil to continue to turn (in the same direction) ;
6(c)(i) evaporation ;
6(c)(ii) the most energetic molecules ;
escape from the surface ;
Question 7:-
Topic – B17.2 Selection
(a) A student investigates antibiotic resistance in one strain of bacteria.
They use five different antibiotics on paper discs.
The antibiotic discs are placed in a Petri dish with the bacteria and left for three days.
Fig. 7.1 shows the results.
Identify the antibiotic in Fig. 7.1 that is most effective against this strain of bacteria.
Give one reason for your answer.
antibiotic ……………………………………
reason …………………………………………………………………………………
(b) The differences in antibiotic resistance in bacteria are caused by random mutation.
(i) State the structure in a cell where mutation occurs.
(ii) State the type of radiation that increases the rate of mutation.
(c) Explain why the development of antibiotic resistance in bacteria is an example of evolution.
▶️Answer/Explanation
Ans :
7(a) B ;
largest clear area / AW ;
7(b)(i) gene / chromosome / nucleus / DNA ;
7(b)(ii) ionising ;
7(c) change in adaptive features (over time) ;
that results from natural selection ;
Question 8:-
Topic – C11.1 Formulas and terminology
Fig. 8.1 shows the structures of three carbon compounds.
(a) Ethene is an unsaturated hydrocarbon.
Explain how the structure of ethene shows that ethene is an unsaturated hydrocarbon.
unsaturated ……………………………………………
hydrocarbon …………………………………………..
(b) Ethene, C2H4, reacts with hydrogen to make an alkane.
Write the balanced symbol equation for this reaction.
(c) Complete the dot‑and‑cross diagram in Fig. 8.2 to show the bonding in ethene.
Only show the outer‑shell electrons.
(d) Ethanol is made by fermentation.
State one condition for making ethanol by fermentation.
(e) Ethanol can also be made from ethene in an addition reaction.
Complete the symbol equation for this reaction.
C2H4 + ……… → C2H5OH
(f) A scientist makes a solution of ethanol.
250cm3 of the solution contains 5.75g of ethanol.
Calculate the concentration of the ethanol solution in mol/dm3.
[Ar: C, 12; H, 1; O, 16]
concentration of ethanol solution = …………………………………… mol/dm3
▶️Answer/Explanation
Ans :
8(a) contains a double (carbon to carbon) bond ;
contains only hydrogen and carbon (atoms) / AW ;
8(b) C2H4 + H2 → C2H6 ;;
8(c) 
8(d) absence of air / no oxygen / anaerobic / yeast / sugar or glucose / water / warm temperature ;
8(e) H2O ;
8(f) (Mr of C2H5OH) = 46 ;
(moles of C2H5OH) = 5.75 ÷ 46 = 0.125 ;
250 cm3 = 250 ÷ 1000 = 0.250 dm3 ;
(concentration of C2H5OH) = 0.125 ÷ 0.25 = 0.5 mol/dm3 ;
Question 9:-
Topic – C2.3 Isotopes
The element strontium has many naturally occurring isotopes, some of which are unstable.
(a) Table 9.1 shows the half‑lives of four unstable isotopes of strontium.
(i) Fig. 9.1 shows a decay curve for one of the isotopes given in Table 9.1.
Determine which isotope of strontium from Table 9.1 would give the data shown in Fig. 9.1.
isotope …………………………………………………
(ii) A scientist purchases a sample of a strontium isotope to use as a radioactive source in a series of experiments.
The scientist estimates that the experiments will take three months to complete.
Suggest which of the isotopes in Table 9.1 would be best for the scientist to purchase.
Explain your suggestion.
isotope ………………………………………………………………………
explanation ………………………………………………………………..
(b) Place ticks (✓) in Table 9.2 to show the nature of a beta particle.
(c) The density of strontium is 2.6g/cm3 .
A sample of strontium has a mass of 7.8g.
Calculate the volume of the sample of strontium.
volume = ………………………… cm3
▶️Answer/Explanation
Ans :
9(a)(i) half-life calculated from graph ;
strontium-82 ;
9(a)(ii) strontium-90 AND it will not need to be replaced for a long time/ will last for a long time / will not run out quickly/owtte ;
9(b) has a negative charge ;
is affected by electric fields AND is affected by magnetic fields ;
9(c) (V=) m/ρ OR 7.8 / 2.6 ;
(V=) 3.0 (cm3) ;
Question 10:-
Topic – B9.4 Blood
(a) Red blood cells are specialised to transport oxygen.
Describe two ways that red blood cells are adapted for their function.
(b) A student investigates the effect of different concentrations of salt solution on red blood cells.
The student immerses the red blood cells in different concentrations of salt solution and observes the cells after immersion.
Table 10.1 shows the results.
(i) Identify the salt solution with the same water potential as red blood cells.
…………………………….. g/dm3
(ii) Explain the observation seen at 10.0g/dm3 in Table 10.1.
(c) The investigation is repeated with plant cells.
(i) Plants cells do not burst when immersed in 2.0g/dm3 salt solution.
Explain why.
(ii) State two uses of water in plant cells.
(iii) State the name of the type of plant cell specialised for absorption of water.
▶️Answer/Explanation
Ans :
10(a) any two from:
no nucleus ;
large surface area / biconcave (shape) ;
contains haemoglobin ;
10(b)(i) 8.0 (g per dm3) ;
10(b)(ii) water leaves the cell ;
by osmosis ;
the salt solution has a lower water potential (than the red blood cell) / water moves from an area of high water potential to
low water potential ;
10(c)(i) presence of cell wall ;
strengthens the cell ;
10(c)(ii) any two from:
solvent ;
photosynthesis ;
support / ref to turgidity / prevent wilting ;
transport of, minerals / mineral ions / ions ;
AVP ;
10(c)(iii) root hair (cell) ;
Question 11:-
Topic – C4.1 Electrolysis
Sulfuric acid is made by the Contact process.
Fig. 11.1 shows part of the Contact process.
(a) A catalyst is used in the Contact process.
Complete Fig. 11.1 to show the two other essential conditions used.
(b) In the Contact process, sulfur dioxide, SO2 , reacts with oxygen, O2 , to make sulfur trioxide,SO3.
2SO2+ O2 ⇔ 2SO3
(i) Calculate the maximum mass of sulfur trioxide that is made from 1.6kg of sulfur dioxide.
[Ar: O, 16; S, 32]
mass of sulfur trioxide = ……………………………………………. kg
(ii) Fig. 11.2 shows the energy level diagram for the reaction to make sulfur trioxide.
Draw and label on Fig. 11.2:
• the energy change in the reaction
• the activation energy of the reaction
▶️Answer/Explanation
Ans :
11(a) 450 °C ;
1–2 atmospheres ;
11(b)(i) (Mr of SO2) = 64 and (Mr of SO3) = 80 ;
(Mass of SO3) = 80⁄64 × 1.6 ;
= 2.0 (kg) ;
11(b)(ii) 
Question 12:-
Topic – P4 Electricity and magnetism
12 Electricity can be generated in different types of power stations.
(a) Table 12.1 gives some information about six types of power station.
(i) Use data from Table 12.1 to explain why electricity generation is negatively impacting the environment.
(ii) Nuclear power stations are very expensive to build.
Apart from cost, state one advantage and one disadvantage of generating electricity using wind compared to nuclear.
advantage ……………………………………………………
disadvantage ……………………………………………….
(iii) Use data from Table 12.1 to calculate the mass of natural gas needed to generate the same electrical energy output as 1kg of nuclear fuel.
mass = …………………………………………….. kg
(b) A coal power station generates electricity at a voltage of 25000V.
A transformer is used to step the voltage up to 132000V for transmission.
(i) The step‑up transformer contains 3000 turns on the primary coil.
Calculate the number of turns on the secondary coil.
number of turns = …………………………………………………
(ii) Explain why electricity is transmitted at a voltage of 132000V and not 25000V.
▶️Answer/Explanation
Ans :
12(a)(i) highest percentage of electricity is generated by, coal (and natural gas) / fossil fuels / 61% of production from fossil fuels or
coal and natural gas / 37% of production from coal / 24% of production from natural gas ;
plus
coal / natural gas / fossil fuels, release, carbon dioxide ;
cause climate change / global warming / enhanced greenhouse effect ;
OR
coal / natural gas / fossil fuels, release sulfur dioxide ;
causes acid rain ;
12(a)(ii) (advantage:) no nuclear, waste / accidents / suitable for small scale / no fuel is used / less set up time / AVP ;
(disadvantage:) only works when wind speed is suitable / is less efficient / need lots of turbines (to generate large amounts of electricity) / noise pollution / AVP ;
12(a)(iii) (nuclear output E per kg =) 5.0 × 105 × 0.93 = 4.65 × 105 (MJ) ;
(gas output E per kg =) 45 × 0.49 = 22.05 (MJ) ;
= 4.65 × 105 / 22.05 = 21 000 (kg) ;
12(b)(i) (Ns =) NpxVs / Vp OR 3000 × 132 000 / 25 000 ;
(Ns =) 16 000 ;
12(b)(ii) (increasing the voltage) reduces the current ;
less, energy / power / heat, loss ;