Question

Identify the following substances:

(1) An acidic gas which gives dense white fumes with NH3
(11 An alkane which can also be called a green house gas.
(iii) A solid which when kept in the open, forms a solution after som
(iv) An alloy used in electrical fittings.
(v) A metal which gives hydrogen gas on reacting with both dilute a
Write equations for the following reactions:
Aluminium oxide and Sodium hydroxide.
(ii) Zine and dilute sulphuric acid.
(
11​

Answer 1

1. HCl is the gas
2. methane
3. deliquescent substances (they absorbs water out of the air until they dissolve themselves into liquid solutions. )
4. brass

equations

Aluminium oxide and Sodium hydroxide react to form water and sodium aluminate

• Al2O3 + 2NaOH → 2NaAlO2 + H2O

Zinc reacts with dilute sulphuric acid to form zinc sulphate and hydrogen gas

• Zn + H2SO4 → ZnSO4 +H2

Answer 2

1) HCl (Hydrochloric acid reacts with NH3 and forms dense fumes)

2) Methane (It is from the group of alkanes and is a green house gas)

3) Deliquescent substance (It is a solid which when kept in open forms a solution after sometime)

4) Brass (It is a solid-in-solid solution used to make electrical fittings)

5) Aluminium

Question 2:

1) Al₂O₃ + 2NaOH ⇒ 2NaAlO₂ (Sodium Aluminate) + H₂O

2) Zn + H₂SO₄ (dilute) => ZnSO₄ (Zinc Sulphate) + H₂