Q1. Balanced equation of Fe + H2O → Fe3O4 + H2 is
(A) Fe + 4H2O → Fe3O4 + H2
(B) Fe + 4H2O → Fe3O4 + 4H2
(C) 3Fe + H2O → Fe3O4 + 4H2
(D) 3Fe + 4H2O → Fe3O4+ 4H2
Q2. The formula of quick lime and the compound formed when it reacts with water respectively are
(A) CaO, CaCO3
(B) CaO, Ca(OH)2
(C) Ca(OH)2, CaCO3
(D) CaCO3, Ca(OH)2
Q3. A solution of which of the following compounds is used for whitewashing?
(A) Slaked lime
(B) Quick Lime
(C) Blue vitriol
Q4. Electrolysis of water is
(A) Combination reaction
(B) Decomposition reaction
(C) Displacement reaction
Q5. Example of displacement reaction is
(A) Fe(s) + CuSO4(aq) → FeSO4(aq) + Cu(s)
(B) C(s) + O2(g) → CO2(g)
(C) AgCl( )s s 2Ag( ) Cl ( ) g Sunlight + 2
(D) BaCl2(aq) + Na2SO4(aq) → BaSO4(s) + 2NaCl(aq)
Q6. Lead nitrate Pb(NO3)2 on heating forms solid Lead oxide (PbO) and Nitrogen dioxide gas. What is the colour of lead oxide and nitrogen dioxide?
(A) White, Colourless
(B) White, Brown
(C) Yellow, Brown
(D) Yellow, Colourless
Q7. Silver chloride on exposure to sunlight decomposes into silver and chlorine gas. This property is used in
(A) Heat production as enormous energy is released.
(B) Silver extraction as earth contains silver mainly in silver chloride form.
(C) Photography as grey silver formed produces an image imprint.
Q8. Quick lime is used in whitewashing because
(A) it is cheap
(B) it forms slaked lime with water which has a nice colour.
(C) it forms slaked lime with water which reacts with atmospheric carbon dioxide to form limestone.
Q9. Example of a double displacement reaction will be
(A) Metal with a salt
(B) Metal with an acid
(C) Metal with metal
(D) Salt with a salt
Q10. Ferrous sulphate solution is green while ferric oxide formed by its decomposition is
Q11. Corrosion or rusting of iron metal is
(A) Oxidation of iron
(B) Reduction of iron
(C) Displacement of iron
Q12. To facilitate the electrolysis of water we add a few drops of acids like sulphuric acid because
(A) It acts as a catalyst
(B) It prevents the decomposition of electrodes used.
(C) It makes the water a good conductor of electricity
Q13. Fried foods are packed with which gas to prevent oxidation of fat?
(C) Any of the above
Q14. Which of the following statements about the given reaction are correct?
3Fe (s) + 4H2O (g) → Fe3O4 (s) + 4H2 (g)
(i) Iron metal is getting oxidised
(ii) Water is getting reduced
(iii) Water is acting as reducing agent
(iv) Water is acting as oxidising agent
(A) (i), (ii) and (iii)
(B) (iii) and (iv)
(C) (i), (ii) and (iv)
(D) (ii) and (iv)
Q15. Which of the following is a displacement reaction?
(A) MgCO3 → MgO + CO2’
(B) 2Na + 2H2O → 2NaOH + H2
(C) 2H2 + O2 → 2H2O
(D) 2Pb (NO3)2 → 2PbO + 4NO2 + O2