(i) Name the main metal used in making of the alloys given below:
(a) Duralumin
(b) Stainless steel

(ii) Differentiate between the following pairs based on the criteria given:
(a) Sulphuric acid and Nitric acid (using barium chloride solution)
(b) Unsaturated and Saturated hydrocarbons (type of bond present)

(iii) Calcium carbonate reacts with dilute hydrochloric acid as given below:
CaCO₃ + 2HCl → CaCl₂ + H₂O + CO₃
(a) What is the mass of 5 moles of calcium carbonate? (Relative molecular mass of calcium carbonate is 100)
(b) How many moles of HCI will react with 5 moles of calcium carbonate?
(c) What is the volume of carbon dioxide liberated at S.T.P. at the same time?

(iv) Identify the gas evolved in each of the following reactions:
(a) Methane undergoes complete combustion.
(b) Copper carbonate is heated.
(c) MnO₂ reacts with concentrated HCl.

Solution

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