IB Chemistry SL R3.1 Proton transfer reactions questions

Exam-style multiple choice and written questions with full markschemes. Check multiple choice answers straight away, or type, photograph or draw a written answer and get it marked.

Question 1

Paper 2Medium5 marks

An aqueous sodium hydrogencarbonate solution is tested with a pH probe. At 25 ∘C25\,^\circ\mathrm{C} the pH is 8.30. At this temperature, neutral water has [H+]=1.00×10−7 mol dm−3[\mathrm{H^+}]=1.00\times10^{-7}\ \mathrm{mol\,dm^{-3}}

A student concludes that HCO3−\mathrm{HCO_3^-} can act only as a Brønsted–Lowry base because the solution is alkaline.

(a)

Calculate [H+][\mathrm{H^+}] in the solution, in mol dm−3\mathrm{mol\,dm^{-3}} to two significant figures.

[1]
(b)

Using your answer to (a), determine whether the solution is acidic, neutral or alkaline.

[1]
(c)

Write equations with state symbols to show HCO3−\mathrm{HCO_3^-} acting as a Brønsted–Lowry acid and as a Brønsted–Lowry base in water. Use the equations to assess the student's conclusion.

[3]

The best questions are still waiting

Unlock every question in this topic, then type, photograph or draw your answer and have it marked against the markscheme. Find out where you are dropping marks.