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4.5 moles of calcium carbonate are reacted with dilute hydrochloric acid. (i) Write the equation for the reaction. (ii) What is the mass of 4.5 moles of calcium carbonate ? (Relative molecular mass of calcium carbonate is 100). (iii) What is the volume of carbon dioxide liberated at stp ? (iv) What mass of calcium chloride is formed ? (Relative molecular mass of calcium chloride is 111). (v) How many moles of HCI are used in this reaction ? |
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Answer» (i) CaCO3 + 2HCl ---> CaCl2 + H2O + CO2 (ii) Mass of 1 more of CaCO3 = 100 g Mass of 4.5 moles of CaCO3 = 4.5 x 100 = 450 g (iii) 1 mole CaCO3 liberates 1 mole of CO2 .'. 4.5 moles of CaCO3 liberates 4.5 moles of CO2 Volume of CO2 liberated at STP = 22.4 x 4.5 = 100.8 l. (iv) 1 mole of CaCO3 gives 1 mole of CaCl2. .'. 4.5 moles of CaCO3 gives 4.5 moles of CaCl2 = 4.5 x 111 = 499.5 g (v) 1 mole of CaCO3 requires 2 moles of HCl 4.5 moles of CaCO3 requires = 2 x 4.5 = 9 moles of HCl |
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