A blue dye solution reacts with bleach solution and becomes colourless. The bleach solution has a concentration of either 0.10 mol/dm3 or 0.20 mol/dm3. The reaction mixture is kept at either 20 ∘C20\ ^\circ\text{C}20 ∘C or 35 ∘C35\ ^\circ\text{C}35 ∘C. Equal volumes of the solutions are used and all other conditions are the same.
Which set of conditions gives the greatest initial rate of reaction?
0.10 mol/dm30.10\ \text{mol/dm}^30.10 mol/dm3 at 20 ∘C20\ ^\circ\text{C}20 ∘C
0.10 mol/dm30.10\ \text{mol/dm}^30.10 mol/dm3 at 35 ∘C35\ ^\circ\text{C}35 ∘C
0.20 mol/dm30.20\ \text{mol/dm}^30.20 mol/dm3 at 35 ∘C35\ ^\circ\text{C}35 ∘C
0.20 mol/dm30.20\ \text{mol/dm}^30.20 mol/dm3 at 20 ∘C20\ ^\circ\text{C}20 ∘C
127 exam-style questions on AQA GCSE Chemistry 6.1 Rate of reaction, covering 6.1.1a Calculating rates of reactions, 6.1.1b Gradient of a tangent as rate, 6.1.2 Factors which affect the rates of chemical reactions, 6.1.3 Collision theory and activation energy, and 6.1.4 Catalysts. Each one has a worked solution and a mark scheme showing where the marks go.