\({\text{300 c}}{{\text{m}}^{\text{3}}}\) of water is added to a solution of \({\text{200 c}}{{\text{m}}^{\text{3}}}\) of \({\text{0.5 mol}}\,{\text{d}}{{\text{m}}^{ - 3}}\) sodium chloride. What is the concentration of sodium chloride in the new solution?

A.     \({\text{0.05 mol}}\,{\text{d}}{{\text{m}}^{ - 3}}\)

B.     \({\text{0.1 mol}}\,{\text{d}}{{\text{m}}^{ - 3}}\)

C.     \({\text{0.2 mol}}\,{\text{d}}{{\text{m}}^{ - 3}}\)

D.     \({\text{0.3 mol}}\,{\text{d}}{{\text{m}}^{ - 3}}\)

C

One respondent stated that it would be best to start HLP1 with a mole type question and that these first three questions could have potentially tripped up candidates at the beginning of this paper. It must be emphasised that P1 covers all topics on the syllabus and, hence, any question can be asked as an Objective 1 or 2 multiple-choice type question based on any of the corresponding AS‟s on Topic 1 - Quantitative Chemistry. As regards the questions themselves, none of these three questions, in fact, posed a significant problem for candidates. 76% of candidates got Q1 correct, 68% Q2 and 78% Q3.