Cambridge IGCSE Sciences - Co-ordinated (Double) 0654 — 2020 Oct/Nov Paper 2 · Variant 3
0654/23/O/N/20 · 40 questions · 40 marks · ≈45 min
The question paper and its mark scheme, free to read here and free to download. This is Cambridge’s own paper, exactly as it was sat.
Question paper16 pages
Mark scheme3 pages
Answers below. Sit the paper first if you are practising.
Questions as text
Q1 · What is not a characteristic of all living organisms?
1 What is not a characteristic of all living organisms? A excretion B growth C photosynthesis D sensitivity
Mark scheme: C
Q2 · The diagrams show four different cells found in living organisms
2 The diagrams show four different cells found in living organisms. 1 2 3 4 Which cell types have a large surface area for diffusion? A 1 and 2 B 1 and 4 C 2 and 3 D 3 and 4
Mark scheme: B
Q3 · What colour does Benedict’s solution change to when heated with a reducing sugar?
3 What colour does Benedict’s solution change to when heated with a reducing sugar? A blue B blue-black C orange D purple
Mark scheme: C
Q4 · A mixture of starch and saliva was set up at four different temperatures
4 A mixture of starch and saliva was set up at four different temperatures. Each mixture was tested with iodine solution after 15 minutes and again after 30 minutes. The results are shown in the table. temperature colour with iodine solution / C 15 minutes 30 minutes 0 blue-black blue-black 15 blue-black brown 35 brown brown 95 blue-black blue-black What do the results suggest? A The enzyme in saliva is inactive at 95 C. B The enzyme in saliva is slow to work at 35 C. C The enzyme in saliva works equally well at 15 C and 35 C. D The enzyme in saliva works faster at higher temperatures.
Mark scheme: A
Q5 · What is the effect of nitrate ion deficiency on plants?
5 What is the effect of nitrate ion deficiency on plants? leaf colour growth A green good B green poor C yellow good D yellow poor
Mark scheme: D
Q6 · Much of the internal surface of the human small intestine is covered with villi
6 Much of the internal surface of the human small intestine is covered with villi. What is the function of villi? A excretion of waste into the intestine B secretion of enzymes into the intestine C to improve blood circulation in the intestine walls D to increase the internal surface area of the intestine
Mark scheme: D
Q7 · Under which conditions will transpiration from a plant be fastest?
7 Under which conditions will transpiration from a plant be fastest? temperature humidity A high high B high low C low high D low low
Mark scheme: B
Q8 · A student breathed gently in and out of the mouth piece of the apparatus shown
8 A student breathed gently in and out of the mouth piece of the apparatus shown. mouth piece tube limewater P Q What were the results after 10 breaths? P Q A clear clear B clear milky C milky clear D milky milky
Mark scheme: D
Q9 · During an experiment, auxin is applied to one side of a shoot just behind the tip
9 During an experiment, auxin is applied to one side of a shoot just behind the tip. What will this stimulate? A decreased cell elongation in all cells B decreased cell elongation on the side with extra auxin C increased cell elongation in all cells D increased cell elongation on the side with extra auxin
Mark scheme: B
Q10 · In human reproduction, which cells are haploid?
10 In human reproduction, which cells are haploid? gametes zygotes v v 00 WwW > v x x v x x
Mark scheme: B
Q11 · The pedigree diagram shows the inheritance of a recessive condition
11 The pedigree diagram shows the inheritance of a recessive condition. key P Q male without condition male with condition R female without condition female with condition Which statements are correct with reference to this condition? 1 P and Q are both heterozygous for the condition. 2 Q and R have different genotypes. 3 P and R have the same genotype. A 1 and 2 only B 1 and 3 only C 2 and 3 only D 1, 2 and 3
Mark scheme: A
Q12 · What is the name given to a unit containing all of the organisms and their environment…
12 What is the name given to a unit containing all of the organisms and their environment interacting together in a given area? A ecosystem B food chain C food web D trophic level
Mark scheme: D
Q13 · Which row about some of the stages of eutrophication is correct?
13 Which row about some of the stages of eutrophication is correct? growth of growth of respiration of concentration of producers decomposers decomposers dissolved oxygen A decreases increases decreases increases B decreases decreases increases increases C increases decreases decreases decreases D increases increases increases decreases
Mark scheme: D
Q14 · A mixture of solid sulfur and solid sodium chloride is added to water and stirred
14 A mixture of solid sulfur and solid sodium chloride is added to water and stirred. Sulfur is insoluble in water. Sodium chloride is soluble in water. Which processes are used to obtain pure sodium chloride from the mixture? A distillation then chromatography B distillation then crystallisation C filtration then chromatography D filtration then crystallisation
Mark scheme: B
Q15 · Which sample contains the most molecules?
15 Which sample contains the most molecules? A 16 dm3 CH4 B 28 dm3 C2H4 C 16 g CH4 D 28 g C2H4
Mark scheme: B
Q16 · Which row describes what happens at the electrodes during electrolysis?
16 Which row describes what happens at the electrodes during electrolysis? at the anode at the cathode A negative ions gain electrons positive ions lose electrons B negative ions lose electrons positive ions gain electrons C positive ions gain electrons negative ions lose electrons D positive ions lose electrons negative ions gain electrons
Mark scheme: B
Q17 · Which process is exothermic?
17 Which process is exothermic? A boiling water B cracking a long chain alkene C decomposition of limestone D identification of hydrogen using a lit splint
Mark scheme: D
Q18 · Magnesium ribbon is reacted with excess dilute hydrochloric acid at 25 C
18 Magnesium ribbon is reacted with excess dilute hydrochloric acid at 25 C. The experiment is repeated at 45 C, using the same mass of magnesium and the same volume and concentration of dilute hydrochloric acid. Which statement explains why the reaction is faster at 45 C? A Collisions between particles at 45 C are less frequent and fewer colliding particles possess the activation energy. B Collisions between particles at 45 C are less frequent and more colliding particles possess the activation energy. C Collisions between particles at 45 C are more frequent and fewer colliding particles possess the activation energy. D Collisions between particles at 45 C are more frequent and more colliding particles possess the activation energy.
Mark scheme: D
Q19 · Which word equation represents a redox reaction?
19 Which word equation represents a redox reaction? A carbon + copper oxide copper + carbon dioxide B hydrochloric acid + potassium hydroxide potassium chloride + water C magnesium carbonate magnesium oxide + carbon dioxide D sodium sulfate + barium nitrate barium sulfate + sodium nitrate
Mark scheme: A
Q20 · Salts are made by reacting dilute hydrochloric acid with four substances
20 Salts are made by reacting dilute hydrochloric acid with four substances. 1 magnesium 2 magnesium carbonate 3 magnesium hydroxide 4 magnesium oxide Which substances produce a gas when reacted with dilute hydrochloric acid? A 1 and 2 B 1 and 3 C 2 and 4 D 3 and 4
Mark scheme: A
Q21 · Which statement about elements in the Periodic Table is correct?
21 Which statement about elements in the Periodic Table is correct? A The density of the elements in Group I increases up the group. B The metallic character of the elements increases across a period from left to right. C The number of protons in the atoms of the elements increases across a period from left to right. D The reactivity of the elements in Group I decreases down the group.
Mark scheme: C
Q22 · Four metals W, X, Y and Z are added to aqueous solutions of their ions
22 Four metals W, X, Y and Z are added to aqueous solutions of their ions. The results are shown. metal Y ions Z ions W ions X ions W reaction reaction no reaction reaction X reaction reaction no reaction no reaction Y no reaction reaction no reaction no reaction Z no reaction no reaction no reaction no reaction What is the order of reactivity? least reactive most reactive A W X Y Z B W Y X Z C Z X Y W D Z Y X W
Mark scheme: D
Q23 · Which process does not produce carbon dioxide?
23 Which process does not produce carbon dioxide? A acid reacting with a metal B acid reacting with sodium carbonate C complete combustion of methane D respiration
Mark scheme: A
Q24 · The Haber process is used to make ammonia
24 The Haber process is used to make ammonia. Which row shows the conditions used in this process? temperature pressure catalyst / C / atm A Fe 250 450 B Fe 450 250 C V2O5 250 450 D V2O5 450 250
Mark scheme: B
Q25 · The Contact process is used to manufacture sulfuric acid
25 The Contact process is used to manufacture sulfuric acid. Which statement about the Contact process is not correct? A A nickel catalyst is used. B Sulfur dioxide reacts with oxygen to form sulfur trioxide. C Sulfur burns to form sulfur dioxide. D Sulfur trioxide dissolves in concentrated sulfuric acid to form oleum.
Mark scheme: A
Q26 · What reacts with ethene to make ethanol?
26 What reacts with ethene to make ethanol? A bromine B hydrogen C steam D yeast
Mark scheme: C
Q27 · Poly(ethene) is made from ethene by the process of addition polymerisation
27 Poly(ethene) is made from ethene by the process of addition polymerisation. Which word describes ethene in this process? A fuel B catalyst C monomer D solvent
Mark scheme: C
Q28 · A concrete block exerts a pressure on the ground
28 A concrete block exerts a pressure on the ground. Which expression is used to calculate the pressure due to the block? A (mass of block) (area of contact with the ground) ( mass of block ) B (area of contact with the ground) C (weight of block) (area of contact with the ground) (weight of block ) D (area of contact with the ground)
Mark scheme: D
Q29 · The diagrams show four uniform beams, each supported by a pivot at its centre
29 The diagrams show four uniform beams, each supported by a pivot at its centre. Which diagram shows a beam that is balanced? A B 1.0 m 0.5 m 1.0 m 0.5 m 2.0 N 4.0 N 2.0 N 2.0 N C D 2.0 m 1.0 m 1.0 m 2.0 m 1.0 N 2.5 N 1.5 N 1.0 N
Mark scheme: A
Q30 · The diagram shows a box of weight 600 N being pulled up a frictionless slope by a force
30 The diagram shows a box of weight 600 N being pulled up a frictionless slope by a force. force Y 5.0 m 3.0 m X 4.0 m How much work is done against gravity in moving the box from X to Y? A 600 J B 1800 J C 24 000 J D 30 000 J
Mark scheme: B
Q31 · Electricity is generated in power stations
31 Electricity is generated in power stations. Many power stations use steam to drive turbines. Which type of power station does not use steam? A chemical energy (fuel) power stations B geothermal energy power stations C hydroelectric energy power stations D nuclear energy power stations
Mark scheme: C
Q32 · Which part of the electromagnetic spectrum is often involved in thermal energy transfer…
32 Which part of the electromagnetic spectrum is often involved in thermal energy transfer by radiation? A infrared B radio C ultraviolet D X-rays
Mark scheme: A
Q33 · The diagram shows the direction of a wave that passes a particle
33 The diagram shows the direction of a wave that passes a particle. The particle is made to vibrate by the wave. The direction of vibration of the particle is shown. direction of wave direction of vibration of particle particle Which row states the type of wave that passes the particle, and gives an example of this type of wave? type of wave example A longitudinal light B longitudinal sound C transverse light D transverse sound
Mark scheme: C
Q34 · The diagram shows a ray of light travelling in glass from point P
34 The diagram shows a ray of light travelling in glass from point P. Angle x is greater than the critical angle. In which labelled direction does the ray continue? A B air glass C x P D
Mark scheme: D
Q35 · In an experiment to investigate induced magnetism, a magnet is brought close to samples…
35 In an experiment to investigate induced magnetism, a magnet is brought close to samples of different unmagnetised materials. A student records the results using diagrams. The teacher checks the diagrams and finds that only one result is correctly recorded. Which result is correctly recorded? A S magnet N N S iron B S magnet N S N steel C S magnet N S N plastic N D S magnet N iron S
Mark scheme: B
Q36 · The current in an ammeter is 1.5 A
36 The current in an ammeter is 1.5 A. How much charge passes through the ammeter in one minute? A 0.025 C B 1.5 C C 40 C D 90 C
Mark scheme: D
Q37 · A heating element in an electric kettle has a resistance of 24
37 A heating element in an electric kettle has a resistance of 24 . When the kettle is connected to a 240 V supply, it takes 2.5 minutes to boil some water. How much energy is used to boil the water? A 16 J B 960 J C 6000 J D 360 000 J
Mark scheme: D
Q38 · Fuses are used in domestic electric circuits
38 Fuses are used in domestic electric circuits. Which statement about fuses is correct? A A fuse is connected in the live wire. B A fuse is connected in the neutral wire. C A 3 A fuse produces a current of exactly 3 A in the circuit. D A 3 A fuse produces a minimum current of 3 A in the circuit.
Mark scheme: A
Q39 · A solenoid carrying a current produces a magnetic field
39 A solenoid carrying a current produces a magnetic field. Which diagram shows the magnetic field pattern? A B current current C D current current
Mark scheme: D
Q40 · Which type of radiation has the greatest ionising effect?
40 Which type of radiation has the greatest ionising effect? A infrared rays B -particles C -particles D -rays
Mark scheme: B
What was in this paper
The subtopics covered by these 40 questions, and how many questions each got. Open one in a new tab to see every Cambridge question on it.
2Energy, work and power2Experimental design2Air quality and climate1Alcohols1Arrangement of elements1Biological molecules1Cell division1Characteristics of living organisms1Coordination and response1Diet1Diffusion1Digestive system1Electrical safety1Electrolysis1Electromagnetic effects1Energy flow1Enzymes1Exothermic and endothermic reactions1Forces1Gas exchange in humans1General properties of waves1Habitat destruction1Light1Monohybrid inheritance1Polymers1Preparation of salts1Pressure1Radioactivity1Rate of reaction1Reactivity series1Redox1Separation and purification1Simple phenomena of magnetism1The mole and the Avogadro constant1Transfer of thermal energy1Transpiration1What you needed in this session
Cambridge’s own grade thresholds for 2020 Oct/Nov, Paper 2 · Variant 3. A higher threshold means an easier paper — the bar moves with how the cohort did.