Changing the concentration of the reactants
2 marks · EasyA student plots a graph showing the initial rate of reaction versus concentration of a reactant. At 0.80 mol/dm³, the rate is 0.011 g/s. Predict the rate if the concentration is increased to 1.60 mol/dm³, assuming the rate is directly proportional to concentration.
Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.
Show answer
0.022 g/s (±0.001)
Common mistakes: Failing to double the rate for doubled concentration
Show mark scheme and worked solution
Marking points
M1 · 1 mark · Identifies that doubling the concentration will double the rate.
A1 · 1 mark · Correctly calculates final rate as 0.022 g/s.
Worked solution
Since concentration doubles (0.80 → 1.60 mol/dm³) and rate is directly proportional, the rate will also double: 0.011 g/s × 2 = 0.022 g/s