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Ammonia can readily dissolve in water according to the equation below:
8.1 Explain why a hydroxide ion is regarded as a Lowry-Brønsted base. (2)
8.2 Identify the type of bond responsible for the formation of the ammonium ion in
the above equation. (1)
8.3 Write a balanced equation to show how the ampholyte in the above equation
will act as a base when it reacts with hydrochloric acid (HCℓ). (2)
5 dm3 of nitric acid (HNO3), with a concentration of 0,75 mol·dm-3 , is spilled accidentally in a small pond of water. The acid and water has a total volume of 1 000 dm3 . To neutralise the acid, calcium hydroxide is added to the water.
2HNO3(aq) + Ca(OH)2(aq)→ Ca(NO3)2(aq) + 2H2O(ℓ)
8.4 Define the term concentration. (2)
8.5 Calculate the concentration of the acid AFTER it was spilled in the pond. (4)
8.6 Use calculations to determine if 120 g of calcium hydroxide will be sufficient
to react completely with ALL the acid in the pond. (6)
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