IGCSE Physical Science MC

The relative molecular mass of carbon dioxide is 44. The relative molecular mass of oxygen is 32. Which statement about the rate of diffusion of these gases at the same temperature is correct?

• Carbon dioxide diffuses faster because its particles move faster.

• Carbon dioxide diffuses faster because its particles move slower.

• Oxygen diffuses faster because its particles move faster.

• Oxygen diffuses faster because its particles move slower.

The diagram shows a piece of apparatus. What is measured using this apparatus?

• mass

• temperature

• time

• volume

Mixture X is separated into its components W and Y by chromatography. E is the distance between the base line and Y. F is the distance between the base line and the top of the paper. G is the distance between the base line and the solvent front. Which equation is used to calculate the Rf value of Y?

• E ÷ F

• E ÷ G

• F ÷ E

• G ÷ E

An isotope of sodium is represented as ²³₁₁Na. Which row represents a different isotope of sodium?

• A: electrons 11, neutrons 13, protons 11

• B: electrons 12, neutrons 12, protons 12

• C: electrons 13, neutrons 12, protons 13

• D: electrons 23, neutrons 12, protons 23

The numbers of protons, neutrons and electrons in particles W, X, Y and Z are shown. Which particles have the same chemical properties?

• W, X and Y

• W and X only

• X, Y and Z

• X and Y only

Three statements about diamond and graphite are listed. 1. They are different solid forms of the same element. 2. They each conduct electricity. 3. They have atoms that form four equally strong bonds. Which statements are correct?

• 1 and 3

• 1 only

• 2 and 3

• 3 only

Ammonia reacts with oxygen to produce substance X and water. An incomplete equation is shown. 4NH₃ + 5O₂ → X + 6H₂O What is the formula of X?

• N₂

• NO

• NO₂

• N₂O

The formulae of three substances are shown. 1. NO₂ 2. C₂H₅OH 3. C₃H₈ Which substances have a relative molecular mass of 46?

• 1, 2 and 3

• 1 and 2 only

• 1 only

• 2 only

Which row describes what happens to the ions at each electrode during electrolysis?

• gain of electrons at anode, loss of electrons at cathode

• gain of electrons at anode, gain of electrons at cathode

• loss of electrons at anode, loss of electrons at cathode

• loss of electrons at anode, gain of electrons at cathode

The energy level diagram for a reaction is shown. Which statements about the energy level diagram are correct?

• 1, 2 and 3

• 1 and 2 only

• 1 only

• 2 and 3 only