An experiment is carried out to measure the rate of reaction between magnesium and dilute hydrochloric acid under two different conditions. The mass of magnesium and the number of moles of hydrochloric acid are the same in both experiments. Graphs of the results are shown. Which statements could explain the difference between graph 1 and graph 2? 1 Graph 1 results are obtained at a higher temperature. 2 Graph 1 results are obtained by using hydrochloric acid that is more concentrated. 3 Graph 1 results are obtained using smaller pieces of magnesium.

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