ALE REVISION

One molecule of the oxide of element Z reacts with six molecules of water to produce an acidic

compound. What is element Z?

• Al

• P

• Na

• S

Which property is not associated with the element sodium?

• It can react with cold water to form hydrogen.

• It forms a basic oxide.

• It forms a neutral chloride

• It is an oxidising agent.

Which properties do compounds of aluminium and silicon have in common?

• Aqueous solutions of their chlorides contain aluminium or silicon cations.

• Their chlorides have co-ordinate bonding.

• Their oxides are amphoteric.

• Their oxides are insoluble in water.

Consecutive elements X, Y and Z are in the third period of the Periodic Table. Element Y has the highest first ionisation energy and the lowest melting point of these three elements.

What could be the identities of X, Y and Z?

• sodium, magnesium, aluminium

• magnesium, aluminium, silicon

• silicon, phosphorus, sulfur

• aluminium, silicon, phosphorus

Which oxide, when mixed with water, will produce the solution with the lowest pH?

• CO₂

• Na₂O

• P₄O₁₀

• SiO₂

Why does aluminium oxide dissolve in sodium hydroxide solution?

• Aluminium oxide can behave as an acid.

• Aluminium oxide can behave as a base.

• The bonding in aluminium oxide is ionic.

• Aluminium oxide has a giant structure.

Which statement about enthalpy changes is correct?

• Enthalpy changes of atomisation are always negative.

• Enthalpy changes of combustion are always positive.

• Enthalpy changes of formation are always positive.

• Enthalpy changes of neutralisation are always negative.

In which set do all the molecules have all their atoms arranged in one plane?

• AlCl₃, BF₃, PH₃

• AlCl₃, CO₂, NH₃

• BF₃, C₂H₄, C₃H₆

• C₂H₄, CO₂, H₂O

Ammonium metavanadate, NH₄VO₃, can be used to make a solution containing VO₂Cl, which contains chloride ions.

What is the change in the oxidation number of vanadium in this reaction?

• -1

• 0

• +1

• +2

In a chemical system the particles involved have a range of energies. This can be shown on a graph called the Boltzmann distribution.

Which statement correctly explains the effect of a catalyst on the particles in a chemical system?

• A catalyst enables particles with a lower energy to collide successfully.

• A catalyst increases the number of particles with higher energies.

• A catalyst increases the number of particles with the most probable energy value.

• A catalyst increases the value of the most probable particle energy.