The sketch below was obtained when 2g of magnesium was reacted with excess of 2M hydrochloric acid. The volume of hydrogen evolved was then plotted...

The sketch below was obtained when 2g of magnesium was reacted with excess of 2M hydrochloric acid. The volume of hydrogen evolved was then plotted against time as shown below:

(a) On the same axis plot the graph that would be obtained if 1M hydrochloric acid was used instead of 2M hydrochloric acid. Explain
(b) Explain the significance of the flat portion BC of the curve

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(a)

-Graph should be less steeper showing lower reaction rate since HCl is less concentrated.


(b) Graph flattens out at BC showing that all the magnesium has been used up, hence, no reaction is taking place and there is therefore no evolution of hydrogen gas. The volume of the gas, therefore, remains constant.

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maurice.mutuku answered the question on October 28, 2019 at 11:15

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