A reaction uses the same solution concentration at 20 °C and 35 °C. A student explains the faster reaction at 35 °C by saying particles are larger and the activation energy has decreased.
Evaluate the explanation.
[4 marks]AQA GCSE Chemistry June 2018 Paper 2H
5 questions on this paper's topics
21:001 of 5
In paper chromatography, dye A travels farther than dye B in the same time. Both start on the same line and the solvent front has passed both spots.
Explain the separation in terms of the mobile and stationary phases, and assess the suggestion that A must be a smaller molecule.
[4 marks]A company claims that because its hydrocarbon fuel burns with no smoke it causes neither acid rain nor climate change. The fuel contains small amounts of sulfur and is burned at high temperature in air.
Evaluate the claim using the possible gaseous products.
[4 marks]Two laboratory ecosystem models both remove carbon dioxide by photosynthesis. In model A all dead plant material decomposes. In model B some material is buried where decomposition is very slow.
Explain which model better represents long-term carbon removal and why the amount photosynthesised alone is not enough to predict the long-term atmospheric change.
[4 marks]A manufacturer labels a product "100% recyclable". Local facilities accept only one of its three joined materials, and separating the materials is costly.
Evaluate whether the label establishes that the product will have a low disposal impact.
[4 marks]