Balance the following chemical equation

Explanation:

4). Ca(NO₃)₂ + Na₂SO₄ → CaSO₄ + 2Na(NO₃)₂

  This question is incorrect.

  Since, the final product by reacting Na⁺⁺ and NO₃⁻⁻ is NaNO₃

  Correct equation will be,

  Ca(NO₃)₂ + Na₂SO₄ → CaSO₄ + 2NaNO₃

  This equation is in the balanced form.

5). Ni(NO₃)₂ + KI → NiI + 2K(NO₃)₂

  Correct equation will be,

  Ni(NO₃)₂ + KI → NiI₂ + 2KNO₃

  [Since final product by reacting Ni⁺⁺ and I⁻ is NiI₂]

  Balanced form of this equation will be,

  Ni(NO₃)₂ + 2KI → NiI₂ + 2KNO₃

6). Ni(NO₃)₂ + KOH → NiOH + K(NO₃)₂

   Correct form of the equation will be

   Ni(NO₃)₂ + KOH → Ni(OH)₂ + KNO₃

   [Since reaction of Ni⁺⁺ and OH⁻ gives Ni(OH)₂ and the reaction of K⁺ and NO₃⁻ gives KNO₃]

   Now balancing this equation,

   Ni(NO₃)₂ + KOH → Ni(OH)₂ + 2KNO₃

                              ↓

  Ni(NO₃)₂ + 2KOH → Ni(OH)₂ + 2KNO₃

the atomic number will stay the same no matter how many electrons it has, so it doesn’t decrease nor increase. it’ll only change with a different number of protons