What is this symbol '⇌' used to represent?
A redox reaction
A reversible reaction
A physical change
What is produced in the backward reaction in this equilibrium, when the reaction goes from right to left: NH4Cl(s) ⇌ NH3(g) + HCl(g)?
NH4Cl(s)
NH3(g) + HCl(g)
NH4Cl(s) + NH3(g) + HCl(g)
What is the main source of the nitrogen used in the manufacture of ammonia?
Coal
Air
Natural gas
What conditions of temperature and pressure are used in the industrial manufacture of ammonia?
Temperature = 450°C, pressure = 200 atmospheres
Temperature = 20°C, pressure = 450 atmospheres
Temperature = 200°C, pressure = 1 atmosphere
The equation for the Haber process is N2 + 3H2 ⇌ 2NH3. What gases will be present at equilibrium?
Nitrogen and hydrogen
Nitrogen, hydrogen and ammonia
Ammonia only
What kind of catalyst is used in the Haber process?
Iron
Platinum
Vanadium(V) oxide
One type of artificial fertilizer can be made by reacting ammonia with nitric acid.
Ammonia + nitric acid → ammonium nitrate
What kind of reaction is this?
Neutralisation
Oxidation
Displacement
At 450°C and 200 atmospheres pressure, the yield of ammonia produced is around 35%. How can the yield of ammonia be increased?
Increase the temperature
Decrease the pressure
Increase the pressure
Which of the following reactions is a positive test for ammonia gas?
Bubble the ammonia through barium nitrate solution - a white precipitate will form
Put a lit splint into a test tube of ammonia gas - the gas will burn with a squeaky pop
Hold a piece of damp red litmus paper in a stream of ammonia gas - the litmus paper will turn blue
Nitrogenous fertilizers can cause increased growth of algae and other aquatic plants. These plants then die, leading to reduction of oxygen levels in the water as the plants are decomposed by bacteria. What name is given to this process?
Eutrophication
Blue baby syndrome
Deoxygenation