1) The nitrogen content of bread was determined using the following procedure:
• A sample of bread weighing 2.80 g was analysed.
• The nitrogen in the sample was converted into ammonia.
• The ammonia was collected in 50.0 mL of 0.125 mol L⁻¹ hydrochloric acid. All of the ammonia was neutralised, leaving an excess of hydrochloric acid.
The excess hydrochloric acid was titrated with 23.30 mL of 0.116 mol L⁻¹ sodium hydroxide solution.
(a) Write balanced equations for the TWO reactions involving hydrochloric acid.

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(b) Calculate the moles of excess hydrochloric acid.

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(c) Calculate the moles of ammonia.

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(d) Calculate the percentage by mass of nitrogen in the bread.

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