The combustion of carbon(ii)oxide in oxygen can be represented by equation. 2CO + O 2 → 2CO 2 Calculate the volume of the resulting mixture at the end of the reaction if 50cm^3of carbon(ii)oxide was exploded in 100cm^3 of oxygen

• A) 75cm^3
• B) 125cm^3
• C) 100cm^3
• D) 50cm^3

The following are major gaseous pollutants except.

• A) CO
• B) CO₂
• C) SO₂
• D) CFC

Given that electronegativity increases across a period and decreases down a group in the periodic table, in which of the following compounds will the molecules be held together by the strongest hydrogen bond?

• A. HF^(g)
• B. NH3^(g)
• C. CH4^(g)
• D. HCl^(g)

The hydroxyl ion concentrated, (OH-), in a solution of sodium hydroxide of pH 10.0 is?

• A. 10-10 mol dm^-3
• B. 10-6 mol dm^-3
• C. 10-4 mol dm^-3
• D. 10-2 mol dm^-3

(a) (i) Define heat of combustion.

(ii) What name is given to the container used for determining tne reaction?

(b) The heat of combustion of carbon in excess air is - 3935 kJ.

(i) Sketch an energy profile diagram for the reaction.

(ii) Calculate the heat change when 60 g of carbon undergoes complete combustion to produce carbon (IV) oxide. (C = 12)

(iii) Explain why the value of the heat of neutralization of strong acids by strong bases is constant.

(c) Give reason for the following:

(i) rusting of iron is regarded as a slow combustion process;

(ii) iron filings rust much more faster than iron nails when exposed to the same atmospheric condition;

(iii) iron is better protected from corrosion by plating it with.zinc than with tin

A given amount of gas occupies 10.0dm5 at 4atm and 273°C. The number of moles of the gas present is [Molar volume of gas at s.t.p = 22.4dm^3]

• A) 0.89 mol
• B) 1.90 mol
• C) 3.80 mol
• D) 5.70 mol

Which of the following is not a direct petroleum product?

• A. Methane
• B. Ethanol
• C. Petrol
• D. Vaseline

Diamond does not conduct electricity because it

• A. has no free valence electrons
• B. is a giant molecule
• C. contains no bonded electrons
• D. is a solid at room temperature

What is the pH of 0.001 mol dm^?3 solution of sodium hydroxide?

• A) 14
• B) 13
• C) 12
• D) 11

The hydrolysis of groundnut oil by potassium hydroxide is known as

• A. hydrogenation
• B. saponification
• C. esteriffication
• D. neutralization