AQA A Level Chemistry Acids and Bases

.The expression for the acid dissociation constant for aqueous ammonium ions is ...The initial concentration of the ammonium chloride solution was 2.00 mol dm-3.Use the pH of this solution, before any sodium hydroxide had been added, to calculate a value for Ka

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How would you work out Q2d please ?Where did they get 4.6 from that they use to find out [H+]

Reply 1

Marr.sar

you use the PH curve. The initial PH of the ammonium chloride is where the graph crosses the y-axis, which is PH 4.6, so the concentration of H+ can now be worked out.