Chem AS 2

Which statement about this distribution curve is correct?

• If the temperature of the gas is increased, the maximum of the curve becomes higher.

• If the temperature of the gas is increased, the maximum of the curve moves to the left.

• 
• 

• An atom of element X needs one extra electron for a full outer shell; an atom of element Y needs three extra electrons for a full outer shell.

• An atom of element Y has five electrons in the 3p subshell.

• Element X has an oxidation number of +7 in most of its compounds.

• When element X combines with element Y, the bonding is ionic.

Which statement about the electrons in a ground state carbon atom is correct?

• Electrons are present in four different energy levels.

• There are more electrons in p orbitals than there are in s orbitals.

• The occupied orbital of highest energy is spherical.

• The occupied orbital of lowest energy is spherical.

In this question you should assume the vapour behaves as an ideal gas.

0.175 g of a volatile liquid produces a vapour of volume 4.50 × 10^–5m³ at 100 °C and pressure of 1.013 × 10⁵Pa.

What is the Mr of the liquid?

• 31.9

• 87.1

• 119

• 127

Which reaction is endothermic?

• Ca(OH)₂(aq) + 2HCl (aq) → CaCl₂(aq) + 2H₂O(l)

• 2Cl (g) → Cl₂(g)

• 2Ca(s) + O₂(g) → 2CaO(s)

• CaCO₃(s) → CaO(s) + CO₂(g)

• The rate of reaction will decrease and the position of the equilibrium will move to the left.

• The rate of reaction will decrease and the position of the equilibrium will move to the right.

• The rate of reaction will increase and the position of the equilibrium will move to the left.

• The rate of reaction will increase and the position of the equilibrium will move to the right.

Which diagram correctly shows the electronegativity of the elements Na, Mg, Al and Si plotted against their first ionisation energies?

• 
• 
• 
• 

The properties of chlorine, bromine and their compounds are compared.

Which property is smaller for chlorine than for bromine?

• bond strength of the hydrogen-halide bond

• first ionisation energy

• solubility of the silver halide in NH₃(aq)

• strength of the van der Waals’ forces between molecules of the element

Solid sodium iodide reacts with concentrated sulfuric acid to form more than one product that contains sulfur.

What is the lowest oxidation number of sulfur in these products?

• -2

• 0

• +4

• +6

Which emission from an internal combustion engine contributes to the erosion of marble statues?

• carbon monoxide

• nitrogen

• nitrogen dioxide

• unburnt hydrocarbons