Nitrogen and Sulphur

Catalytic converters are fitted in the exhaust systems of many cars.

Which gas:

● causes acid rain if it is released into the air

● is removed from car exhaust fumes by a catalytic converter?

• carbon dioxide

• carbon monoxide

• hydrocarbon vapour

• nitrogen dioxide

Which statement is correct?

• Ammonia reacts with alkalis to form the ammonium ion.

• Ammonium chloride contains ionic, covalent and co-ordinate bonds

• The ammonium ion reacts with acids to produce ammonia.

• The bond angle in the ammonium ion is approximately 107°.

At 550 °C nitrogen dioxide reacts with unburnt hydrocarbon fragments such as CH₃ in the catalytic converter of a motor vehicle.

4CH₃ + 7NO₂ → 3.5N₂ + 4CO₂ + 6H₂O

Which row gives the energy change for this reaction and a possible reason for it?

• A

• B

• C

• D

Ammonium sulfate, (NH₄)₂SO₄, and ammonium nitrate, NH₄NO₃, are used as fertilisers.

These salts have different percentages by mass of nitrogen. They have the same effect as each other on the pH of wet neutral soil.

Which row is correct?

• A

• B

• C

• D

Which processes involve the conversion of sulphur dioxide into sulphur trioxide?

• the combustion of sulphur contaminated carbonaceous fuels

• the Contact process for manufacturing sulphuric acid

• the catalytic oxidation of sulphur dioxide by oxides of nitrogen

Ammonia and chlorine react as shown.

8NH₃ + 3Cl₂ → N₂ + 6NH₄Cl

Which statements are correct?

• Each nitrogen atom is oxidised

• Each chlorine atom is reduced.

• Ammonia behaves as a base.

Which gas is present in the exhaust fumes of a car engine in a much greater amount than any other gas?

• carbon dioxide

• carbon monoxide

• nitrogen

• water vapour

Sulfur dioxide and sulfites are used in food preservation.

Why are they used for this purpose?

• They are reducing agents which slow down the oxidation of food.

• They inhibit the growth of aerobic bacteria.

• They react with NO₂(g) converting it to NO(g).

In a car engine, non-metallic element X forms a pollutant oxide Y.

Further oxidation of Y to Z occurs in the atmosphere. In this further oxidation, 1 mol of Y reacts with ½ mol of gaseous oxygen.

What can X be?

• carbon

• nitrogen

• sulfur

Ammonia exists as simple covalent molecules, NH₃. Ammonia can react with suitable reagents to form products containing ammonium ions, NH₄⁺. Ammonia can also react with suitable reagents to form products containing amide ions, NH₂^–.

Which of these nitrogen-containing species are present in an aqueous solution of ammonia?

• ammonia molecules, ammonium ions and amide ions

• ammonia molecules and ammonium ions only

• ammonia molecules only

• ammonium ions only