Equal masses of magnesium ribbon were reacted separately with equal volumes of 1M hydrochloric acid and 1M methanoic acid. The results were plotted on a...

Equal masses of magnesium ribbon were reacted separately with equal volumes of 1M hydrochloric acid and 1M methanoic acid. The results were plotted on a graph as shown below. Two curves X and Y were obtained.


a) Explain which curves represents:
i) 1M hydrochloric acid.
ii) 1M Methanoic acid.

b) State the significance of point Z.

c) Write ionic equation for the reaction between magnesium and dilute hydrochloric acid.

d) Calculate the maximum mass of the gas that would be liberated if 1.2g of magnesium reacted with excess hydrochloric acid.
(Mg = 24, H =1).

e) Calculate the volume of the gas produced in (e) above at r.t.p (molar gas volume at r.t.p) = 24dm³.

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a) X – Hydrochloric Acid X is a strong Acid

Y – Methanoic Acid is a weak acid.

b) End of the reaction.

c)

d)

e) moles of H₂ = 0.05
volume of H₂ = 0.05 x 24
= 1.2 litres or 1200 cm³

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maurice.mutuku answered the question on September 20, 2019 at 06:18

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