CHEMISTRY ADDA: X Formative assessments Chemical reaction and equations

Q1. The given equation represents the reaction of sodium metal with water.

Sodium + Water Sodium hydroxide + Hydrogen

Which of the following chemical equations represents a complete balanced chemical equation for the given word equation?

A. 2Na(s) + H2O → 2NaOH(aq) + H2(g)
B. Na(s) + 2H2O → NaOH(aq) +2H2(g)

C. 2Na(s) + 2H3O → 2NaOH(aq) + 2H2(g)
D. 2Na(s) + 2H2O → 2NaOH(aq) + H2(g)

Q2. Identify the chemical equation which represents a complete balanced equation for the reaction of barium chloride with sodium sulphate to produce barium sulphate and sodium chloride.

A. BaCl2(aq) + Na2SO4 (aq) → BaSO4(s) + 2NaCl(aq)v

B. BaCl2(aq) + Na2SO4 (aq) → 2BaSO4(s) + 2NaCl(aq)

C. 2BaCl2(aq) + Na2 → SO4 (aq) 2BaSO4(s) + NaCl(aq)

D. BaCl2(aq) + Na2 → SO4 (aq) BaSO4(s) + NaCl(aq)

Q3. Ferric oxide reacts with aluminum to produce aluminum oxide and iron. The balanced chemical equation for the given reaction is
Fe2O3 + 2Al → Al2O3 + 2Fe

Which of the following substances is oxidized in the given reaction?

A. Al2O3
B. Fe2O3
C. A1
D. Fe

Q4. White silver chloride changes to grey in sunlight because of the formation of silver metal along with the evolution of chlorine gas. Identify the chemical equation that gives a correct representation of the process.

A. 2AgCl   → 2Ag + Cl2
B. AgCl →   Ag + Cl2
C. 2Ag + Cl2   → 2AgCl
D. Ag + Cl2   →   2AgCl

Q5. When copper oxide is treated with hydrogen gas copper is produced along with water. The balanced chemical equation for the given reaction is CuO + H2 → Cu + H2O Which substance is oxidized in the given reaction?

A. H2
B. Cu
C. H2O
D. CuO

Q6. The balanced chemical equation for the reaction of nitrogen with hydrogen to produce

Ammonia gas is-

A. N2(g) + H2(g) → 2NH3(g)
B. 2N2(g) + H2(g) → 2NH3(g)

C. N2(g) + 3H2(g) → 2NH3(g)
D. 2N2(g) + H2(g) → 2NH3(g)

Q7. Identify the chemical equation that correctly represents production of magnesium nitrideby burning magnesium metal in a pure nitrogen atmosphere from the following–

A. Mg3N2(s) ® Mg(g) + N2(g) B. Mg + N2 ® Mg3N2

C. 3Mg(g)N2(g) ®Mg3N2(g) D. Mg3N2 ® 3Mg + N2

Q8. Which of the following reactions represents a combination reaction?

A. CaO(s) + H2O(g) ® Ca(OH)2(aq) B. CaCO3(s) ® CaO(s) + CO2(g)

C. Zn + CuSO4(aq) ® ZnSO4(aq) + Cu(s) D. 2FeSO4(s) ® Fe2O3(s) + SO2(g) + SO3(g)

Q9. Which of the following reactions represents a double displacement reaction?

A. BaCl2(aq) + Na2SO4(aq) ® BaSO4(s) + 2NaCl(aq)

B. 2FeSO4(s) ® Fe2O3(s) + SO2(g) + SO3(g)

C. 2Pb(NO3)2(g) ® 2PbO(s) + 4NO2(g) + O2(g)

D. Zn(s) + 2AgNO3(aq) ®Zn(NO3)2(aq) + 2Ag(s)

Q10. The reaction: Fe2O3(s) + 2Al(s) ®Al2O3(s) + 2Fe(s) is an example of a–

A. combination reaction
B. double displacement reaction

C. decomposition reaction
D. displacement reaction

Q10. What happens when dilute hydrochloric acid is added to iron fillings?

A. Hydrogen gas and iron chloride are produced
B. Chlorine gas and hydroxide are produced

C. heat is absorbed, i.e. test tube becomes cold.
D. Iron salt and water are produced

Q. Write balanced chemical equations for the following word equations:

A. Calcium hydroxide + Carbon dioxide Calcium carbonate + Water