Thursday, 9 May 2019

assignment lesson 1 chemistry class10


CHEMICAL REACTIONS AND EQUATIONS
Q1) Prove that the following reactions are redox. Also find oxidizing and reducing agent
4NH3 + 5O2 → 4NO + 6H2O , 3Fe + 4H2O→ Fe3O4 + 4H2
Q2) Which of the following are exotherminc/endothermic process? Give reason
1.       Reaction of water with quick lime      2. Dilution of an acid           3. Evaporation of water                     4. Sublimation of camphor
Q3) Identify the reducing agent in the following reactions
1.       4NH3 + 5O2 → 4NO + 6H2O                2.H2O + F2 → HF + HOF   3. Fe2O3 + 3CO → 2Fe + 3CO2              4. 2H2 + O2 → 2H2O
Q4) Identify the oxidizing agent (oxidant) in the following reactions
1.       Pb3O4 + 8HCl → 3PbCl2 + Cl2 + 4H2O     2. 2Mg + O2 → 2MgO 3. CuSO4 + Zn → Cu + ZnSO4       4. V2O5 + 5Ca → 2V + 5CaO
Q5) A magnesium ribbon is burnt in oxygen to give a white compound X accompanied by emission of light. If the burning ribbon is now placed in an atmosphere of nitrogen, it continues to burn and forms a compound Y.
1.       Write the chemical formulae of X and Y
2.       Write a balanced chemical equation, when X is dissolved in water.
Q6) Zinc liberates hydrogen gas when reacted with dilute hydrochloric acid, whereas copper does not. Explain, why?
Q7) What happens when a piece of
1.       Zinc metal is added to copper sulphate solution
2.       Aluminium metal is added to dilute hydrochloric acid
3.       Silver metal is added to copper sulphate solution
Also , write the balanced chemical equation, if reaction occurs
Q8) You are provided with two containers made up of copper and aluminium. You are also provided with solutions of dilute HCl, dilute HNO3, ZnCl2 and H2O. In which of the containers these solutions can be kept
Q9) Balance the following chemical equation and identify the type of chemical reaction
1.       Mg + Cl2 → MgCl2   2. HgO → Hg + O2         3. Na + S → Na2S 4. TiCl4 + Mg → Ti + MgCl2                 5. CaO + SiO2 → CaSiO3  6. H2O2 → H2O + O2
Q10) Why silver chloride turns grey when exposed to sunlight