Question

V.
Complete following equations
1. K + H2O →
2. Mg + H2SO4 →
3. Zn + HCl →
4. Al + NaOH →
5. Pb + KOH →
​

Answer 1

Answer:

1. 2K + 2H2O → 2KOH + H2

2. Mg + H2SO4 →MgSO4 + H2

3. Zn + 2HCl →ZnCl2 + H2

4. 2Al + 2NaOH → 2NaAlO2 + H2

5. Pb + KOH →K2PbO2 + H2

Explanation:

1. 2K + 2H2O → 2KOH + H2

We know that potassium metal reacts with moisture and water rapidly so we kept the Potassium metal in the kerosene. When potassium metal reacts with water it produces potassium hydroxide and releases hydrogen gas which is very inflammable gas.

2. Mg + H2SO4 →MgSO4 + H2

We know that if a metal reacts with an acid it produces a metallic salt and releases hydrogen gas. Here, when Magnesium reacts with sulphuric acid to produce a metallic salt called magnesium sulphate and releases hydrogen gas which is an inflammable gas.

3. Zn + 2HCl →ZnCl2 + H2

We know that if a metal reacts with an acid it produces a metallic salt and releases hydrogen gas. Here, when Zinc reacts with Hydrochloric acid to produce a metallic salt called zinc chloride and releases hydrogen gas which is an inflammable gas.

4. 2Al + 2NaOH → 2NaAlO2 + H2

We know that Aluminium is an amphoteric element that can reacts with both acids and bases to produce salt and release hydrogen gas. We also know that when an amphoteric element reacts with sodium hydroxide or other strong bases to produce a salt and releases hydrogen gas. When aluminium metal reacts with Sodium Hydroxide to produce sodium zincate as a salt and release hydrogen gas.

5. Pb + KOH →K2PbO2 + H2

We know that Lead is an amphoteric element that can reacts with both acids and bases to produce salt and release hydrogen gas. We also know that when an amphoteric element reacts with Potassium hydroxide or other strong bases to produce a salt and releases hydrogen gas. When lead metal reacts with Potassium Hydroxide to produce Potassium metaplumate as a salt and release hydrogen gas.