2024 Y2 WA2 Revision

Select all factors that would cause rate of diffusion to be lower.

• higher temperature

• smaller difference in concentration

• higher surface area to volume ratio

• larger particles

• decrease density of the medium

Which shows the correct match of name of reaction to the chemical equation? (Select all that apply)

• Name: Photosynthesis

  Chemical equation:

  C₆H₁₂O₆ + 6O₂ --> 6CO₂ + 6H₂O

• Name: Respiration

  Chemical equation:

  6CO₂ + 6H₂O --> C₆H₁₂O₆ + 6O₂

• Name: Combustion

  Chemical equation:

  C + O₂ --> CO₂

• Name: Neutralisation

  Chemical equation:

  HNO₃ + KOH --> KNO₃ + H₂O

• Name: Thermal decomposition

  Chemical equation:

  ZnCO₃ --> ZnO + CO₂

Explain why electrolysis of water is a chemical change while evaporation of water is a physical change.

Which is/are true? (Select all that apply)

• NH₃ gas can turn dry red litmus paper blue

• alkalis taste bitter and feel soapy

• acids can conduct electricity

• alkalis would cause universal indicator to turn from green to orange

• acids have pH < 7

The pH value of a solution is 6.

Which natural indicator shown in the diagram will be able to prove that the solution is acidic?

• A

• B

• C

• D

A car moves forward with a forward force of 300 N. Which statement can be true about the resistive forces acting on the car and the resultant speed of the car?

• If resistive forces is 300 N, the car will stop.

• If resistive forces is 300 N, the car will move at constant speed.

• If resistive forces is 200 N, the car will increase speed.

• If resistive forces is 200 N, the car will slow down.

• If resistive forces is 400 N, the car will slow down.

The mass of a woman is 50 kg. Assuming that the surface area of her sole is 0.01 m², what is the pressure she exerts on the ground when standing on one foot?

• 0.5 Pa

• 5 Pa

• 5000 Pa

• 50 000 Pa

Which correctly describes the changes in the types of energy?

• A

• B

• C

• D

The block has a weight of 500 N, what is the gravitational potential energy gained by the block? Assume no air resistance.

Define "Osmosis".