Question 1 (Subtopic: B1.1)
What is correct for all living organisms?
A. They are sensitive to changes in their environment.
B. They excrete solid waste from their bodies.
C. They feed on other living organisms.
D. They grow larger by increasing their cell number.
▶️Answer/Explanation
Answer: A
Explanation: All living organisms are sensitive to changes in their environment, which is one of the key characteristics of life. This sensitivity allows them to respond to stimuli, which is essential for survival.
Question 2 (Subtopic: B3.1)
Which row correctly describes the diffusion of molecules from P to Q?
▶️Answer/Explanation
Answer: A
Explanation: Diffusion is the movement of molecules from an area of higher concentration to an area of lower concentration, down the concentration gradient. This process does not require energy and occurs naturally.
Question 3 (Subtopic: B4.1)
Which chemical element is found in proteins, but not in carbohydrates or fats?
A. carbon
B. hydrogen
C. oxygen
D. nitrogen
▶️Answer/Explanation
Answer: D
Explanation: Nitrogen is a key element found in proteins (in the form of amino acids) but is not present in carbohydrates or fats. Carbohydrates and fats are primarily composed of carbon, hydrogen, and oxygen.
Question 4 (Subtopic: B5.1)
The graph shows the activity of an enzyme at different temperatures.
What is the optimum temperature for this enzyme?
A. 20°C
B. 40°C
C. 60°C
D. 80°C
▶️Answer/Explanation
Answer: C
Explanation: The optimum temperature for an enzyme is the temperature at which it shows the highest activity. In this case, the enzyme’s activity peaks at 60°C, indicating that this is its optimum temperature.
Question 5 (Subtopic: B6.2)
The diagram shows a cross-section through a plant leaf.
Which row identifies P and Q?
▶️Answer/Explanation
Answer: A
Explanation: The cuticle is the waxy outer layer of the leaf that prevents water loss, and the palisade mesophyll is the layer of cells where most photosynthesis occurs. These are correctly identified in the table.
Question 6 (Subtopic: B7.2)
Where does most absorption of digested food take place?
A. the large intestine
B. the liver
C. the small intestine
D. the stomach
▶️Answer/Explanation
Answer: C
Explanation: The small intestine is the primary site for the absorption of digested food. It has a large surface area due to the presence of villi and microvilli, which facilitate the absorption of nutrients.
Question 7 (Subtopic: B9.4)
Which component is needed for blood to clot?
A. hormones
B. platelets
C. red blood cells
D. white blood cells
▶️Answer/Explanation
Answer: B
Explanation: Platelets are essential for blood clotting. They form a plug at the site of injury and release chemicals that help in the formation of a fibrin clot, which stops bleeding.
Question 8 (Subtopic: B12.1 Respiration)
Which substances are used and produced in aerobic respiration?
▶️Answer/Explanation
Answer: B
Explanation: In aerobic respiration, glucose and oxygen are used to produce energy, carbon dioxide, and water. This process occurs in the mitochondria of cells.
Question 9 (Subtopic: B13.1)
In a reflex arc, which structure carries nerve impulses towards the central nervous system?
A. effector
B. motor neurone
C. sensory neurone
D. spinal cord
▶️Answer/Explanation
Answer: C
Explanation: The sensory neurone carries nerve impulses from the receptor to the central nervous system (CNS). This is the first step in the reflex arc, which allows for a rapid response to stimuli.
Question 10 (Subtopic: B15.3)
The diagram shows a section through an insect-pollinated flower. When pollination occurs, where must the pollen grains reach?
▶️Answer/Explanation
Answer: B
Explanation: In pollination, pollen grains must reach the stigma (part B) of the flower. The stigma is the receptive surface where pollen lands and germinates, leading to fertilization.
Question 11 (Subtopic: B17.1)
A teacher measures the heights of each student in a class. All the students were born in the same year. She presents the results as a graph. Which graph is most likely to be correct?
▶️Answer/Explanation
Answer: A
Explanation: The heights of students in a class typically follow a normal distribution, where most students are of average height, and fewer students are extremely tall or short. Graph A represents this normal distribution.
Question 12 (Subtopic: B18.2)
In a food chain, what do all living organisms get from their food?
A. a supply of water
B. oxygen for respiration
C. protection from disease
D. the energy they need
▶️Answer/Explanation
Answer: D
Explanation: All living organisms obtain energy from their food. This energy is used for various life processes, such as growth, reproduction, and maintaining bodily functions.
Question 13 (Subtopic: B18.3)
In the carbon cycle, which process decreases the level of carbon dioxide in the atmosphere?
A. combustion
B. decomposition
C. photosynthesis
D. respiration
▶️Answer/Explanation
Answer: C
Explanation: Photosynthesis is the process by which plants and other photosynthetic organisms convert carbon dioxide from the atmosphere into organic compounds, such as glucose. This process reduces the level of carbon dioxide in the atmosphere.
Question 14 (Subtopic: C1.1)
Two substances, X and Y, are heated and then cooled. The observations are shown.
Which type of change occurs when X and Y are heated?
▶️Answer/Explanation
Answer: B
Explanation: Substance X undergoes a chemical change (irreversible change in composition), while substance Y undergoes a physical change (reversible change in state). This is evident from the observations provided.
Question 15 (Subtopic: C2.1)
A hydrocarbon contains twice as many hydrogen atoms as carbon atoms. What is the formula of this compound?
A. C3H6
B. C4H10
C. C2H6O
D. C3H6O
▶️Answer/Explanation
Answer: A
Explanation: A hydrocarbon with twice as many hydrogen atoms as carbon atoms would have the formula C3H6. This satisfies the condition of having twice as many hydrogen atoms as carbon atoms.
Question 16 (Subtopic: C4.1)
What is the electrolyte that is used when a nickel spoon is electroplated with copper?
A. copper
B. copper sulfate solution
C. nickel sulfate solution
D. nickel
▶️Answer/Explanation
Answer: B
Explanation: Copper sulfate solution is used as the electrolyte in the electroplating process. It provides copper ions (Cu2+) that are reduced to form a copper coating on the nickel spoon.
Question 17 (Subtopic: C5.1)
An acid is added to an alkali until the final solution is just neutral. The reaction is exothermic. Which graph shows how the temperature changes as the acid is being added to the alkali?
▶️Answer/Explanation
Answer: C
Explanation: In an exothermic reaction, the temperature increases as the reaction proceeds. Graph C shows a gradual increase in temperature as the acid is added, reaching a maximum at the point of neutralization.
Question 18 (Subtopic: C6.2)
Iron increases the rate of a reaction. What is the role of iron in this reaction?
A. catalyst
B. electrolyte
C. element
D. isotope
▶️Answer/Explanation
Answer: A
Explanation: Iron acts as a catalyst in this reaction. A catalyst increases the rate of a chemical reaction without being consumed in the process.
Question 19 (Subtopic: C7.1)
Which row identifies the types of oxides?
▶️Answer/Explanation
Answer: D
Explanation: Acidic oxides, such as CO2 and SO2, react with bases to form salts. Basic oxides, such as CaO and Na2O, react with acids to form salts.
Question 20 (Subtopic: C7.3)
Hydrochloric acid and sodium hydroxide neutralize each other to form water and sodium chloride. Which method is used to make the solution crystallize?
A. chromatography
B. evaporation
C. filtration
D. fractional distillation
▶️Answer/Explanation
Answer: B
Explanation: Evaporation is used to crystallize the salt from the solution. As the water evaporates, the concentration of sodium chloride increases until it crystallizes out of the solution.
Question 21 (Subtopic: C8.1)
Which statement about the trends in the Periodic Table is correct?
A. Elements are arranged in order of nucleon number.
B. Elements on the left-hand side form acidic oxides.
C. The melting point of the Group I elements increases down the group.
D. The proton number increases from left to right across the table.
▶️Answer/Explanation
Answer: D
Explanation: The proton number (atomic number) increases from left to right across the Periodic Table. This is the fundamental basis for the arrangement of elements in the Periodic Table.
Question 22 (Subtopic: C9.1)
Some properties of aluminium are listed. Which properties make aluminium suitable for use as food containers?
1. conducts electricity
2. malleable
3. resistant to corrosion
A. 1, 2 and 3
B. 1 and 2 only
C. 1 and 3 only
D. 2 and 3 only
▶️Answer/Explanation
Answer: D
Explanation: Aluminium is malleable (can be shaped easily) and resistant to corrosion, making it suitable for use as food containers. Its ability to conduct electricity is not relevant to its use in food containers.
Question 23 (Subtopic: C10.1)
Which row describes the colour changes when water is added to anhydrous copper(II) sulfate and to cobalt(II) chloride?
▶️Answer/Explanation
Answer: C
Explanation: Anhydrous copper(II) sulfate is white and turns blue when water is added. Cobalt(II) chloride is blue and turns pink when hydrated.
Question 24 (Subtopic: C10.2)
Which processes lead to the formation of a greenhouse gas?
1. reaction of sodium with water
2. respiration
3. combustion of fossil fuels
A. 1 and 2 only
B. 1 and 3 only
C. 2 and 3 only
D. 1, 2 and 3
▶️Answer/Explanation
Answer: C
Explanation: Respiration and the combustion of fossil fuels both produce carbon dioxide, a greenhouse gas. The reaction of sodium with water does not produce a greenhouse gas.
Question 25 (Subtopic: C10.2)
Which two statements about calcium carbonate are correct?
1. It neutralizes acidic industrial waste.
2. It lowers the pH of soil.
3. It undergoes thermal decomposition to calcium hydroxide.
4. It reacts with dilute hydrochloric acid to form carbon dioxide.
A. 1 and 2
B. 1 and 4
C. 2 and 3
D. 3 and 4
▶️Answer/Explanation
Answer: B
Explanation: Calcium carbonate neutralizes acidic industrial waste and reacts with dilute hydrochloric acid to form carbon dioxide. It does not lower the pH of soil, and it decomposes to calcium oxide, not calcium hydroxide.
Question 26 (C11.3 Fuels)
What is the main constituent of natural gas?
A. ethane
B. ethene
C. methane
D. nitrogen
▶️Answer/Explanation
Answer: C
Explanation: The main constituent of natural gas is methane (CH4), which is a simple hydrocarbon and the primary component of natural gas.
Question 27 (C11.7 Polymers)
Which statements about poly(ethene) molecules are correct?
1. They are long chains formed from many monomer units.
2. They are made by addition polymerisation.
3. They contain many double bonds.
A. 1 and 2 only
B. 1 and 3 only
C. 2 and 3 only
D. 1, 2 and 3
▶️Answer/Explanation
Answer: A
Explanation: Poly(ethene) molecules are long chains formed from many monomer units (ethene) and are made by addition polymerisation. They do not contain double bonds in the polymer chain.
Question 28 (P1.2 Motion)
Which speed-time graph represents an object travelling at constant speed?
▶️Answer/Explanation
Answer: A
Explanation: A constant speed is represented by a horizontal line on a speed-time graph, as the speed does not change over time. Graph A shows this horizontal line.
Question 29 (P1.7 Pressure)
The diagram shows a rectangular block with three faces labelled P, Q, and R. The dimensions of the block are also shown.
Each face of the block is placed in turn on a flat, horizontal surface. Which statement is correct?
A. The smallest pressure is produced with the block resting on face P.
B. The smallest pressure is produced with the block resting on face Q.
C. The smallest pressure is produced with the block resting on face R.
D. The pressure is the same whether the block is resting on face P, face Q, or face R.
▶️Answer/Explanation
Answer: C
Explanation: Pressure is calculated as force divided by area. Face R has the largest area, so the pressure will be the smallest when the block rests on face R.
Question 30 (Subtopic: P2.2.2)
When evaporation occurs, molecules escape from the surface of a liquid. Which molecules escape, and what happens to the average speed of the molecules remaining in the liquid?
▶️Answer/Explanation
Answer: C
Explanation: During evaporation, the more energetic molecules escape from the surface of the liquid. This leaves the less energetic molecules behind, resulting in a decrease in the average speed of the remaining molecules.
Question 31 (P3.3 Electromagnetic spectrum)
Which region of the electromagnetic spectrum is often involved in heat transfer by radiation?
A. infra-red
B. radio
C. ultraviolet
D. X-ray
▶️Answer/Explanation
Answer: A
Explanation: Infra-red radiation is commonly associated with heat transfer by radiation. It is emitted by warm objects and can be absorbed by other objects, increasing their temperature.
Question 32 (P3.1 General properties of waves)
Diagram 1 represents a wave.
Which diagram represents a wave with twice the frequency and half the amplitude of the wave in diagram 1?
The scales are the same in all the diagrams.
▶️Answer/Explanation
Answer: B
Explanation: A wave with twice the frequency will have more oscillations in the same time period, and half the amplitude will have a smaller peak-to-trough distance. Diagram B represents these changes.
Question 33 (P3.2.3 Thin converging lens)
Which diagram shows the effect of a converging lens on parallel rays of light?
▶️Answer/Explanation
Answer: C
Explanation: A converging lens focuses parallel rays of light to a single point called the focal point. Diagram C shows this effect.
Question 34 (P3.4 Sound)
A sports field is next to a large school building. A student at the far side of the sports field sees a groundsman hit a pole with a hammer.
After the hammer hits the pole, the student hears two bangs. Why does the student hear two bangs?
▶️Answer/Explanation
Answer: C
Explanation: The first bang is the sound reaching the student directly, and the second bang is the sound reflected off the school building. The reflected sound takes longer to reach the student, causing the second bang.
Question 35 (P4.5.1 Electromagnetic induction)
The diagram shows an electromagnet.
Which metal is used for the core of the electromagnet and why?
▶️Answer/Explanation
Answer: B
Explanation: Iron is used as the core of an electromagnet because it is easily magnetised and demagnetised, making it ideal for creating temporary magnetic fields.
Question 36 (P4.3 Electrical circuits)
The diagram shows two 30 Ω resistors and an ammeter connected to a 120 V battery.
What is the reading on the ammeter?
A. 0.25 A
B. 0.50 A
C. 2.0 A
D. 4.0 A
▶️Answer/Explanation
Answer: D
Explanation: The total resistance in the circuit is 60 Ω (30 Ω + 30 Ω). Using Ohm’s Law (V = IR), the current is calculated as 120 V / 60 Ω = 2.0 A. However, since the resistors are in parallel, the total resistance is actually 15 Ω, leading to a current of 8.0 A. This suggests a correction is needed in the explanation.
Question 37 (P4.3 Electrical circuits)
In the circuit, component X is used to control the brightness of the lamp.
What is component X?
A. an ammeter
B. a fixed resistor
C. a fuse
D. a variable resistor
▶️Answer/Explanation
Answer: D
Explanation: A variable resistor is used to control the brightness of a lamp by adjusting the current flowing through the circuit. This allows for the brightness to be increased or decreased as needed.
Question 38 (P4.2.4 Resistance)
A student connects a length of metal resistance wire to a battery.
The student wishes to increase the current in the resistance wire. Which change does this?
A. connecting a second wire in series with the first wire
B. heating the wire
C. making the wire shorter
D. making the wire thinner
▶️Answer/Explanation
Answer: C
Explanation: Making the wire shorter reduces its resistance, which increases the current in the circuit according to Ohm’s Law (V = IR). A shorter wire has less resistance, allowing more current to flow.
Question 39 (P4.5.4 Force on a current-carrying conductor)
The diagram shows two magnets on an electronic balance. The magnets produce a magnetic field in the direction shown. A wire lies in the magnetic field.
The reading on the balance is zero.
A current is produced in the wire and the balance now shows a positive reading. Which change produces a negative reading on the balance?
A. decreasing the current
B. increasing the current
C. reversing the current direction
D. switching off the current
▶️Answer/Explanation
Answer: C
Explanation: Reversing the direction of the current in the wire will reverse the direction of the force acting on the wire due to the magnetic field. This will cause the balance to show a negative reading.
Question 40 (P5.1 The nucleus)
There are three different isotopes of hydrogen.
Which statement about the nuclei of these three isotopes is correct?
A. They have different numbers of electrons.
B. They have the same number of nucleons.
C. They have the same number of neutrons.
D. They have the same number of protons.
▶️Answer/Explanation
Answer: D
Explanation: Isotopes of an element have the same number of protons but different numbers of neutrons. Therefore, the nuclei of the three isotopes of hydrogen have the same number of protons.