Two experiments were carried out as follows and the volume of hydrogen gas evolved measured at intervals of 10 seconds for 100 seconds.

Two experiments were carried out as follows and the volume of hydrogen gas evolved measured at intervals of 10 seconds for 100 seconds.
i) 8cm of magnesium ribbon was added to 1M HCl(aq)
(ii) 8cm of magnesium ribbon was added to 0.5M HCl(aq)
Graphs of volume of hydrogen gas evolved against time were plotted as shown below.

a) Which of the graphs was obtained for reaction (i). Explain.
(b) Explain the general shape of the graphs.

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(a) B – Acid had higher concentration
(b) The reaction rate is initially high because of high concentration but decreases steadily as
concentration also decreases.

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sharon kalunda answered the question on March 29, 2019 at 11:35

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