Question 1 (B6.1)
What do plants need for their nutrition?
A. carbon dioxide, ions, organic compounds and light
B. carbon dioxide, ions, organic compounds and water
C. carbon dioxide, ions, light and water
D. carbon dioxide, organic compounds, light and water
▶️Answer/Explanation
Answer: C
Explanation: Plants require carbon dioxide for photosynthesis, ions (minerals) for growth and development, light as an energy source for photosynthesis, and water for photosynthesis and transport of nutrients. They do not require organic compounds from external sources as they produce their own through photosynthesis.
Question 2 (B2.1)
The diagram shows two cells.
Which row matches the name of each type of cell with its function?
▶️Answer/Explanation
Answer: D
Explanation: Cell 1 is a red blood cell (round shape) which functions in oxygen transport. Cell 2 is a root hair cell (elongated with hair-like projection) which functions in absorption of water and minerals. Ciliated cells are found in the trachea, not roots, and egg cells are not involved in transport.
Question 3 (B4.1)
Which result with the biuret test shows that protein is present?
A. blue
B. green
C. orange
D. purple
▶️Answer/Explanation
Answer: D
Explanation: The biuret test turns purple in the presence of proteins due to the formation of a copper-peptide complex. Blue indicates no protein, while green and orange are not typical results of this test.
Question 4 (B5.1)
A test-tube containing a starch-amylase mixture is incubated at 35°C. The graph shows how the amount of starch in the test-tube changes over the next five minutes.
Which graph shows what happens if a similar starch-amylase mixture is incubated at 100°C?
▶️Answer/Explanation
Answer: A
Explanation: At 100°C, the amylase enzyme would denature (lose its 3D structure and function), so no starch would be broken down. The graph would show all starch remaining (horizontal line at maximum level).
Question 5 (B6.1)
Green plants need magnesium ions. Which plant process is limited when magnesium is deficient?
A. meiosis
B. photosynthesis
C. pollination
D. respiration
▶️Answer/Explanation
Answer: B
Explanation: Magnesium is a central component of chlorophyll, the pigment essential for photosynthesis. Without sufficient magnesium, chlorophyll production is impaired, directly limiting photosynthesis.
Question 6 (B7.1)
Which diet would be most likely to prevent anaemia and rickets?
A. high in calcium and vitamin C
B. high in calcium and vitamin D
C. high in iron and vitamin C
D. high in iron and vitamin D
▶️Answer/Explanation
Answer: D
Explanation: Iron prevents anaemia (needed for hemoglobin), while vitamin D prevents rickets (helps calcium absorption for bone development). Vitamin C helps iron absorption but doesn’t prevent rickets, and calcium alone doesn’t prevent anaemia.
Question 7 (B8.1)
The diagrams show sections through a stem and a root.
Which indicate the positions of the xylem?
A. P and S
B. P and T
C. Q and S
D. Q and T
▶️Answer/Explanation
Answer: B
Explanation: In stems, xylem is typically located toward the center (P), while in roots it forms a central star shape (T). Phloem would be located toward the outside in both organs.
Question 8 (B12.1)
What are the products of the anaerobic respiration of glucose in yeast?
A. alcohol and carbon dioxide
B. alcohol only
C. lactic acid and carbon dioxide
D. lactic acid only
▶️Answer/Explanation
Answer: A
Explanation: Yeast undergoes alcoholic fermentation, producing ethanol (alcohol) and CO₂. Lactic acid is produced in human muscle cells during anaerobic respiration, not yeast.
Question 9 (B13.1)
Auxin is a chemical involved in phototropism of plant shoots. When light shines on one side of a plant, the shoot will grow towards it. This is caused by the effect of auxin on cell elongation. Which row is correct?
| where most auxin is found | effect on elongation | |
|---|---|---|
| A | bright side | inhibits |
| B | bright side | stimulates |
| C | shaded side | inhibits |
| D | shaded side | stimulates |
▶️Answer/Explanation
Answer: D
Explanation: Auxin accumulates on the shaded side of a shoot and stimulates cell elongation, causing the shoot to bend toward light. It does not inhibit growth on either side.
Question 10 (B15.4)
Sexual reproduction involves the fusion of cells.
Which row shows the types of cells involved and what the fusion produces?
▶️Answer/Explanation
Ans: A
Question 11 (B16.1)
What causes phenotypic variation?
A. both environmental and genetic factors
B. environmental factors only
C. genetic factors only
D. neither environmental nor genetic factors
▶️Answer/Explanation
Answer: A
Explanation: Phenotypic variation is caused by both genetic factors (inherited traits) and environmental factors (such as nutrition, climate, and lifestyle). The interaction between these factors determines an organism’s observable characteristics.
Question 12 (B18.2)
Which statement about how organisms get their energy is not correct?
▶️Answer/Explanation
Answer: C
Explanation: Green plants get their energy from sunlight through photosynthesis, not from minerals. Minerals are used as nutrients but are not an energy source.
Question 13 (B19.1)
The list shows changes that occur in a lake which is polluted by nitrogen-containing fertiliser.
- decomposers feed on plants
- growth of algae increases on the lake’s surface
- oxygen levels decrease in the lake
- underwater plants die
In which order do these changes occur?
A. 2 → 4 → 1 → 3
B. 2 → 3 → 4 → 1
C. 3 → 4 → 2 → 1
D. 3 → 4 → 1 → 2
▶️Answer/Explanation
Answer: A
Explanation: The correct sequence is: (2) fertiliser causes algae growth → (4) algae block sunlight killing plants → (1) decomposers break down dead plants → (3) decomposers use up oxygen, causing levels to drop.
Question 14 (C1.1)
Which observation shows that a substance is pure water?
A. It boils between 100°C and 102°C.
B. It melts at 0°C and boils at 100°C.
C. It turns copper(II) sulfate from white to blue.
D. It turns cobalt(II) chloride from pink to blue.
▶️Answer/Explanation
Answer: B
Explanation: Pure substances have sharp melting and boiling points. Water’s exact melting (0°C) and boiling (100°C) points at standard pressure confirm its purity. The other options test for water presence but don’t confirm purity.
Question 15 (C6.1)
Which processes are chemical changes?
- conversion of steam to liquid water
- cracking of alkanes
- fractional distillation of petroleum
- thermal decomposition of calcium carbonate
A. 1 and 3
B. 1 and 4
C. 2 and 3
D. 2 and 4
▶️Answer/Explanation
Answer: D
Explanation: (2) Cracking breaks large hydrocarbons into smaller ones (chemical change). (4) Thermal decomposition breaks calcium carbonate into calcium oxide and carbon dioxide (chemical change). (1) and (3) are physical changes.
Question 16 (C2.6)
Silicon(IV) oxide has a giant molecular structure. Which row is correct?
| number of oxygen atoms bonded to each silicon atom | number of silicon atoms bonded to each oxygen atom | |
|---|---|---|
| A | 2 | 2 |
| B | 2 | 4 |
| C | 4 | 2 |
| D | 4 | 4 |
▶️Answer/Explanation
Answer: C
Explanation: In silicon(IV) oxide, each silicon atom forms 4 covalent bonds with oxygen atoms, and each oxygen atom forms 2 covalent bonds with silicon atoms, creating a giant covalent structure.
Question 17 (C3.2)
What is the definition of the relative atomic mass, Ar, of an element?
A. the average mass of atoms of the element on a scale in which an atom of 12C has a mass of exactly 12 units
B. the average mass of atoms of the element on a scale in which an atom of 1H has a mass of exactly 1 unit
C. the average mass of atoms of the element on a scale in which an atom of 12C has a mass of exactly 1 unit
D. the mass in grams of one mole of atoms of the element
▶️Answer/Explanation
Answer: A
Explanation: Relative atomic mass is defined as the average mass of atoms of an element compared to 1/12th the mass of a carbon-12 atom, making carbon-12 exactly 12 on this scale.
Question 18 (C4.1)
Which particle is oxidised at the anode during the electrolysis of aqueous copper(II) sulfate using inert electrodes?
A. Cu2+
B. H+
C. OH–
D. SO42-
▶️Answer/Explanation
Answer: C
Explanation: Hydroxide ions (OH–) are oxidized at the anode, losing electrons to form oxygen gas and water: 4OH– → O2 + 2H2O + 4e–.
Question 19 (C6.2)
A 2 cm strip of magnesium ribbon, painted on one side, is placed in dilute hydrochloric acid. The apparatus is shown.
The total volume of gas produced is measured.
The experiment is repeated using a 2 cm strip of unpainted magnesium ribbon. The same volume and concentration of dilute hydrochloric acid is used.
What is the rate of the reaction and the total volume of hydrogen produced in the second reaction compared to the first reaction?
| rate | total volume | |
|---|---|---|
| A | faster | greater |
| B | faster | same |
| C | same | greater |
| D | same | same |
▶️Answer/Explanation
Answer: B
Explanation: Unpainted magnesium reacts faster because more surface area is exposed to the acid. However, the total volume of hydrogen depends on the amount of magnesium (same in both cases), not the rate.
Question 20 (C7.1)
An acid neutralises solution X. A neutral solution is formed. What are the pH values of solution X and of the neutral solution?
| pH of solution X | pH of neutral solution | |
|---|---|---|
| A | 2 | 7 |
| B | 2 | 12 |
| C | 12 | 2 |
| D | 12 | 7 |
▶️Answer/Explanation
Answer: D
Explanation: For an acid to neutralize solution X, X must be alkaline (pH 12). The neutral solution formed has pH 7. This is the only option where the initial solution is basic and the product is neutral.
Question 21 (C12.3)
Which diagram shows the correct way to set up the apparatus for chromatography?
▶️Answer/Explanation
Answer: C
Explanation: In chromatography, the spot of ink should be above the solvent level to prevent immediate dissolution. The solvent moves up the paper by capillary action, separating the components of the ink. Option C correctly shows this setup with the spot above the solvent.
Question 22 (C8.1)
Which statement about the Periodic Table is correct?
A. Elements are listed in order of neutron number
B. Elements are listed in order of nucleon number
C. Elements are listed in order of proton number
D. Elements are listed in order of relative atomic mass
▶️Answer/Explanation
Answer: C
Explanation: The Periodic Table arranges elements in order of increasing proton number (atomic number), which determines an element’s identity. This organization creates periodic trends in chemical properties.
Question 23 (C9.3)
Zinc is mixed with molten element X. A new material, Y, is made. Y conducts electricity.
Which type of substance is Y?
A. alloy
B. covalent compound
C. macromolecule
D. ionic compound
▶️Answer/Explanation
Answer: A
Explanation: When zinc is mixed with another molten metal, the resulting material is an alloy. Alloys are metallic mixtures that retain electrical conductivity due to their delocalized electrons.
Question 24 (C9.6)
Tin is extracted from cassiterite (tin oxide). The process involves two reactions.
reaction 1 carbon + oxygen → carbon monoxide
reaction 2 carbon monoxide + tin oxide → carbon dioxide + tin
Which statement about the process is correct?
A. Carbon is higher than tin in the reactivity series
B. Carbon monoxide is formed in reaction 1 by complete combustion
C. Carbon monoxide is reduced in reaction 2
D. Cassiterite is oxidised in reaction 2
▶️Answer/Explanation
Answer: A
Explanation: Carbon can reduce tin oxide because it is more reactive than tin (higher in the reactivity series). The carbon monoxide formed in reaction 1 is from incomplete combustion, and it acts as the reducing agent in reaction 2 where tin oxide is reduced.
Question 25 (C10.2)
Which reaction does not occur in a catalytic converter?
A. 2CO + O₂ → 2CO₂
B. CO₂ + C → 2CO
C. 2NO + 2CO → N₂ + 2CO₂
D. 2NO → N₂ + O₂
▶️Answer/Explanation
Answer: B
Explanation: Catalytic converters reduce harmful emissions by converting CO to CO₂ and NO to N₂. The reverse reaction (CO₂ + C → 2CO) would produce carbon monoxide and doesn’t occur in converters.
Question 26 (C11.1)
Which diagram represents a molecule of ethane?
▶️Answer/Explanation
Answer: C
Explanation: Ethane (C₂H₆) is a saturated hydrocarbon with single bonds between all atoms. Option C correctly shows two carbon atoms single-bonded to each other and each bonded to three hydrogen atoms.
Question 27 (C11.4)
One molecule of hydrocarbon Q undergoes complete combustion to produce four molecules of carbon dioxide. Hydrocarbon Q has no effect on the colour of bromine water.
What is hydrocarbon Q?
A. butane
B. butene
C. propane
D. propene
▶️Answer/Explanation
Answer: A
Explanation: Four CO₂ molecules indicate a 4-carbon hydrocarbon. No reaction with bromine water suggests it’s saturated (alkane). Butane (C₄H₁₀) fits both criteria.
Question 28 (P1.5.1)
What cannot be changed by a force acting on a body?
A. the mass of the body
B. the motion of the body
C. the shape of the body
D. the size of the body
▶️Answer/Explanation
Answer: A
Explanation: Mass is an intrinsic property of matter that doesn’t change with force. Forces can change motion (B), shape (C), and size (D) through acceleration or deformation, but not mass.
Question 29 (P1.5.1)
Diagram 1 shows a spring with its length indicated. Diagram 2 shows the same spring with a 20 N load hung from it, and the new length of the spring.
The spring obeys Hooke’s Law.
Which graph is the extension-load graph for the spring?
▶️Answer/Explanation
Answer: D
Explanation: For a spring obeying Hooke’s Law, extension is directly proportional to load until the elastic limit. Graph D shows this linear relationship, with extension increasing steadily with load.
Question 30 (P1.6.1)
A force acts on an object and moves it a certain distance in the direction of the force. The force is now doubled and the distance increases by a factor of 3. What happens to the work done by the force on the object?
A. It increases by a factor of 1.5
B. It doubles
C. It increases by a factor of 3
D. It increases by a factor of 6
▶️Answer/Explanation
Answer: D
Explanation: Work done = force × distance. Doubling force (×2) and tripling distance (×3) means work increases by 2×3 = 6 times. The factors multiply together.
Question 31 (P2.2.2)
Which statement about evaporation of a liquid is correct?
A. Evaporation causes heating of the liquid
B. Evaporation has no effect on the temperature of the liquid
C. Evaporation is the result of the less-energetic molecules escaping from the surface of the liquid
D. Evaporation occurs more quickly if the surface area of the liquid is increased
▶️Answer/Explanation
Answer: D
Explanation: Evaporation occurs when molecules at the surface of a liquid gain enough energy to escape into the gas phase. Increasing the surface area provides more opportunities for molecules to escape, thus increasing the rate of evaporation. The process of evaporation actually cools the remaining liquid as the more energetic molecules leave.
Question 32 (P2.3.1)
Which statement describes the conduction of thermal energy through a metal bar?
A. Atoms at the hot end move to the cold end
B. Atoms at the hot end vibrate and hit atoms at the cold end
C. Free electrons move from the hot end and collide with atoms further along the rod
D. Free electrons vibrate and pass energy on to their neighbours
▶️Answer/Explanation
Answer: C
Explanation: In metals, thermal energy is conducted primarily by free electrons. These electrons gain kinetic energy at the hot end, move through the metal, and collide with atoms further along the rod, transferring energy. While atoms do vibrate more at the hot end, they don’t move along the rod – it’s the energy that gets transferred through collisions.
Question 33 (P3.1)
An experiment is set up to investigate the motion of particles floating on water in a tank. A wave passes along the water surface from left to right. What happens to the floating particles?
A. They do not move
B. They move up and down
C. They move only to the left
D. They move only to the right
▶️Answer/Explanation
Answer: B
Explanation: Water waves are transverse waves where the particles move perpendicular to the direction of wave propagation. The floating particles will move in circular orbits – up and down as the wave passes – but they don’t travel horizontally with the wave. The wave energy moves left to right while the particles oscillate vertically.
Question 34 (P3.2.2)
A glass block is surrounded by air. Light travelling in the glass block reaches the edge of the block. The critical angle of the glass is 42°.
Which row shows an angle of incidence (i) of the light and what happens to the light when it reaches the edge of the glass block at this angle of incidence?
| i | what happens to the light | |
|---|---|---|
| A | 30° | totally internally reflected |
| B | 45° | refracted |
| C | 60° | totally internally reflected |
| D | 75° | refracted |
▶️Answer/Explanation
Answer: C
Explanation: Total internal reflection occurs when light travels from a denser medium to a less dense medium (glass to air) and the angle of incidence is greater than the critical angle (42° in this case). At 60° (greater than 42°), total internal reflection occurs. At angles less than the critical angle (30°), the light refracts out of the glass.
Question 35 (P3.4)
Which row gives the properties of a sound wave that affect the pitch and the loudness of a sound?
| pitch | loudness | |
|---|---|---|
| A | amplitude | amplitude |
| B | amplitude | frequency |
| C | frequency | amplitude |
| D | frequency | frequency |
▶️Answer/Explanation
Answer: C
Explanation: The pitch of a sound is determined by its frequency – higher frequency means higher pitch. Loudness is determined by the amplitude of the sound wave – greater amplitude means louder sound. These are fundamental properties of sound waves that our ears detect to perceive different sounds.
Question 36 (P4.2.4)
A wire of a certain length has a resistance of 8.0Ω. A second wire made of the same material has double the length and double the cross-sectional area of the first wire.
What is the resistance of the second wire?
A. 4.0Ω
B. 8.0Ω
C. 16Ω
D. 32Ω
▶️Answer/Explanation
Answer: B
Explanation: Resistance (R) is given by R = ρL/A where ρ is resistivity, L is length, and A is cross-sectional area. If length doubles, resistance would double, but if area also doubles, resistance would halve. The two effects cancel out: (2L)/(2A) = L/A, so resistance remains 8.0Ω.
Question 37 (P4.3.2)
Which row shows how lamps are connected in a lighting circuit in a house and gives an advantage of connecting them in this way?
| how lamps are connected | advantage of connecting them in this way | |
|---|---|---|
| A | in parallel | they can be switched separately |
| B | in parallel | they share the voltage |
| C | in series | they can be switched separately |
| D | in series | they share the voltage |
▶️Answer/Explanation
Answer: A
Explanation: Household lighting circuits use parallel connections because: (1) each lamp gets the full mains voltage (they don’t share voltage), (2) if one lamp fails, others remain lit, and (3) each lamp can be controlled by its own switch independently of others. Series connections would mean all lamps share voltage and would all go out if one failed.
Question 38 (P4.4)
An electrical extension block has four sockets, a cable which can safely take a current of 6A and a plug. It is protected by a fuse rated at 5A.
The extension block is used with four appliances and the 5A fuse blows. The owner replaces the 5A fuse with a 13A fuse. Why is the extension block now dangerous?
A. The appliances may overheat before the fuse blows
B. The cable may overheat before the fuse blows
C. The sockets may burn out before the fuse blows
D. The 13A fuse may blow too soon
▶️Answer/Explanation
Answer: B
Explanation: The cable is only rated for 6A, but with a 13A fuse, currents up to 13A could flow before the fuse blows. At currents above 6A, the cable would overheat (possibly causing a fire) while the fuse would still be intact. Fuses must be rated at or below the safe current capacity of the weakest component in the circuit.
Question 39 (P4.5.6)
A transformer with an efficiency of 100% has an input current of 10A. The input voltage is 100V and the output voltage is 20V. What is the output current?
A. 2.0A
B. 10A
C. 50A
D. 200A
▶️Answer/Explanation
Answer: C
Explanation: For a 100% efficient transformer: Power in = Power out. Input power = Vin × Iin = 100V × 10A = 1000W. Therefore output power must be 1000W = Vout × Iout = 20V × Iout. Solving gives Iout = 1000W/20V = 50A. The transformer steps down the voltage but steps up the current.
Question 40 (P5.2.2)
Which type of radiation has the greatest ionising effect, and which is the most penetrating?
| greatest ionising effect | most penetrating | |
|---|---|---|
| A | α-particles | α-particles |
| B | α-particles | γ-rays |
| C | γ-rays | α-particles |
| D | γ-rays | γ-rays |
▶️Answer/Explanation
Answer: B
Explanation: Alpha particles (α) have the greatest ionizing power because they are relatively large and carry a double positive charge, but they are the least penetrating (stopped by paper). Gamma rays (γ) are the most penetrating (require thick lead or concrete to stop) but have the least ionizing power as they are electromagnetic waves with no charge.