Nitrogen & Sulfur (CIE A Level Chemistry)

What happens when silver chloride dissolves in aqueous ammonia?

Oxygen and nitrogen are consecutive elements in Period 2 and both form diatomic molecules.

The bond length in the O₂ bond is 1.21 A and the bond length in N₂ is 1.09A. 

What best explains the difference in bond length?

Which statement about ammonia is completely correct?

“Photochemical smog is produced when    1    acts on    2    and    3   .”

Which row correctly identifies 1, 2 and 3?

Lime, CaO, is used to reduce the acidity of soil, and ammonium nitrate is a nitrogenous fertiliser.

Why can they not be used in a mixed form?

In which of the following reactions does the product produced turn damp litmus paper blue?

Atmospheric oxides and unburned hydrocarbons cause the production of peroxyacetyl nitrate (PAN). 

Which of the following is unaffected by this reaction?

Chlorine react with ammonia in the gas phase.

8NH₃ + 3Cl₂  N₂ + 6NH₄Cl

Which statements are correct?

Farmers often use ammonium chloride as a fertiliser to supply the growing plants with nitrogen in the form of ammonia.  

Which of the following would reduce ammonium chloride’s effectiveness as a fertilizer?

Modern cars have catalytic converters fitted to their exhaust pipes. Despite this, analysis of exhaust gases shows small quantities of nitrogen oxides.

Which amendments would result in lower concentrations of nitrogen oxides in exhaust fumes?

In a car exhaust, multiple reactions take place as molecules are mixed with oxygen at high temperatures. 

Which of the following reactions has the highest enthalpy change? 

Which reaction using ammonia does not involve the nitrogen atom’s non-bonding pair of electrons?

A farmer spreads lime on land which has already been treated with an ammonium nitrate fertilizer.

Which reactions will occur in the treated soil?

Use of the data booklet is relevant to this question. 

Car exhausts release pollutant gases including oxides of nitrogen.

In cities, when a car travels one kilometre, it releases 0.23 g of an oxide of nitrogen N_xO_y, which occupies 120 cm³.

What are the values of x and y?

(Assume 1 mol of gas molecules occupies 24.0 dm³.)

Oxide X is a pollutant which contains a non-metallic element Y, formed in a car engine.

Further oxidation of Y to Z occurs in the atmosphere. In this further oxidation, 1 mol of Y reacts with 0.5 mol of gaseous oxygen molecules. 

Y could be either nitrogen or sulfur. 

Which statements about X, Y and Z can be correct in all possibilities?

Ammonium sulfate in the soil is slowly oxidised by air, producing sulfuric acid, nitric acid and water as the only products. 

How many moles of oxygen gas are needed for the complete oxidation of one mole of ammonium sulfate?

Aqueous ammonia is added to aqueous sulphur dioxide until just alkaline.

Which salt is produced in this reaction?

In a car engine, non-metallic element P forms a pollutant oxide Q. Q can be further oxidised to R.

Two students made the following statements.

Student 1: The oxidation number of P increases by 1 from Q to R.

Student 2: The molecule of Q contains lone pairs of electrons.

P could be carbon or nitrogen or sulfur. 

Which student could be correct if P were any of these elements?

The gases nitrogen dioxide (NO₂) and sulfur trioxide (SO₃) are required during the formation of acid rain.

In a simulation experiment, the pressure of sulfur trioxide gas was 2 atm in a reaction chamber of 600 cm³ and kept at a constant temperature of 25 °C. 0.75 moles of nitrogen dioxide is added to the reaction chamber as well as water vapour.

How many moles of nitrogen dioxide will be in the reaction chamber after all the sulfur trioxide has reacted to make acid rain?

After manufacture in a laboratory, ammonia needs to be dried before being collected.

Which drying agents may be used to dry ammonia?