Available Answers

1. 1.

   Calculate and write the valency of following elements:

   S.No.	Element	Formula	Valency
   1.	Magnesium in magnesium chloride	MgCl2
   2.	Carbon in carbon dioxide	CO2
   3.	Carbon in methane	CH4
   4.	Nitrogen in ammonia	NH3
   5.	Phosphorus in phosphorus trichloride	PCl3
   6.	Zinc in zinc oxide	ZnO

2. 2.

   Work and make formulas for the following:

   1. Copper (II) chloride ___________________
   2. Aluminium oxide  ___________________
   3. Ferric oxide  ___________________
   4. Magnesium nitride  ___________________
   5. Barium thiosulphate  ___________________
3. 3.

   Write the names for the following:

   1. Ba(OH)₂ ___________________
   2. Fe₂O₃ ___________________
   3. Ag₂S ___________________
   4. AuCl₃ ___________________
   5. Cr₂O₃ ___________________
4. 4.

   Write the names using Roman numerals:

   1. Ag₂O ___________________
   2.  FeO ___________________
   3. Hg₂l₂ ___________________
   4. MnO₂ ___________________
   5. Pb(NO₃)₂ ___________________
5. 5.

   Match the following chemical formulas with their chemical names:

   Iron (II) carbonate  Potassium permanganate  Magnesium nitride  Manganese (IV) oxide  Ferric sulphate  Chromium oxide  Ammonium phosphate  Auric chloride

   Mg3N2   Fe2(SO4)3  FeCO3  KMnO4 (NH4)3PO4  AuCl3  Cr2O3  MnO2

6. 6.

   Balance the following equations:

   1. Fe + Cl₂ → FeCl₃ ___________________
   2. Cu(NO₃)₂ → CuO + NO₂ +O₂ ___________________
   3. (NH₄)₂Cr₂O₇ → Cr₂O₃ + H₂O + N₂ ___________________
   4. Al + O₂  → Al₂O₃  ___________________
   5. ZnS + O₂ → ZnO + SO₂ ___________________
   6. N₂ + H₂ → NH₃ ___________________
   7. Mg(NO₃)₂ + KOH → Mg(OH)₂ + KNO₃ ___________________
   8. Fe + O₂ → Fe₃O₄ ___________________
   9. KMnO₄ + H₂SO₄ → K₂SO₄ + MnSO₄ + H₂O + O₂ ___________________
   10. C₆H₁₂ + O₂ → CO₂ + H₂O ___________________