silver can displace copper from copper sulphate solution. Ans. (a) (i) 2H2O Electrolysis 2H2 (g) + O2 (ii) CaCO3 Heat CaO + CO2 (iii) 2AgBr Sunlight 2Ag + Br2 (b) Copper can displace silver from AgNO3 because copper is more reactive than Ag, e.g. Cu + 2AgNO3 (aq) Cu (NO3)2 (aq) + 2Ag (s) Q2.(a) A metal nitrate on heating gives yellowish brown colored metal oxide along with ‘A’ brown gas and a colorless gas Identify and ‘B’ ‘C’. ‘A’ ‘B’ ‘C’. (b) Write the type of reaction. (c) Write balanced chemical equation for the reaction taking place. (d)How is a decomposition reaction is different from combination reaction ? Ans. (a)Metal nitrate is lead nitrate ( Pb(NO3)2) , is nitogen dioxide(NO2) and is ‘A’ ‘B’ ‘C’ oxygen gas. (b) this is a decomposition reaction (c) 2Pb(NO3)2 (s) Heat 2PbO (s) + 4NO2 (g) + O2 (g) …… Lead Nitrate Lead (II) oxide Nitrogen dioxide Oxygen (yellowish colour) (Colourless) ‘A’ ‘B’ ‘C’ (d) in decomposition reaction a single reactant breaks down to form two or more products whereas in combination reaction two or more reactants react to form a single product.
silver can displace copper from copper sulphate solution. Ans. (a) (i) 2H2O Electrolysis 2H2 (g) + O2 (ii) CaCO3 Heat CaO + CO2 (iii) 2AgBr Sunlight 2Ag + Br2 (b) Copper can displace silver from AgNO3 because copper is more reactive than Ag, e.g. Cu + 2AgNO3 (aq) Cu (NO3)2 (aq) + 2Ag (s) Q2.(a) A metal nitrate ‘A’ on heating gives yellowish brown colored metal oxide along with brown gas ‘B’ and a colorless gas ‘C’. Identify ‘A’ ‘B’ and ‘C’. (b) Write the type of reaction. (c) Write balanced chemical equation for the reaction taking place. (d)How is a decomposition reaction is different from combination reaction ? Ans. (a)Metal nitrate ‘A’ is lead nitrate ( Pb(NO3)2) , ‘B’ is nitogen dioxide(NO2) and ‘C’ is oxygen gas. (b) this is a decomposition reaction (c) 2Pb(NO3)2 (s) Heat 2PbO (s) + 4NO2 (g) + O2 (g) …… Lead Nitrate Lead (II) oxide Nitrogen dioxide Oxygen ‘A’ (yellowish colour) (Colourless) ‘B’ ‘C’ (d) in decomposition reaction a single reactant breaks down to form two or more products whereas in combination reaction two or more reactants react to form a single product.
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