A circuit board takes less time to etch when the solution is at 40 °C rather than at 20 °C. The increased fraction of successful collisions accounts for part of this difference.
Give the other change in particle collisions at 40 °C that increases the rate of etching.
A rigid process chamber contains the reacting gases R and S. Before the reaction starts, more gas R is pumped into the chamber. The volume of the chamber, the amount of gas S and the temperature do not change. The pressure in the chamber increases.
Explain why the initial rate of reaction increases.
Two batches use the same reaction to make product P.
Batch 1 contains 5.0 g of reactant X. Batch 2 contains 4.5 g of reactant X and 0.5 g of a catalyst. Both batches contain enough of the other reactant for all the X to be used up.
A technician expects both batches to make the same mass of P because each batch contains a total of 5.0 g of X and catalyst.
Explain why the technician is incorrect.
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.