Translate the following statement into chemical equation and then balance them. Potassium metal reacts with water to give potassium hydroxide and hydrogen gas.

The balanced chemical equation is: 2 K ( s ) + 2 H 2 O ( l ) → 2 K O H ( a q ) + H 2 ( g ) A balanced equation is an equation for a chemical reaction in which the number of atoms for each element in the reaction and the total charges is the same for both the reactants and the products. The equation is balanced by the hit and trial method. It always follows the Law of Conservation of mass .

Translate the following statement into chemical equation and then balance them. Hydrogen sulphide gas burns in air to give water and sulphur dioxide.

The balanced chemical equation for the reaction of hydrogen sulphide gas in air is: 2 H 2 S g Hydrogen sulphide + 3 O 2 g Oxygen → 2 H 2 O l Water + 2 SO 2 g sulphur dioxide A balanced equation is an equation for a chemical reaction in which the number of atoms for each element in the reaction and the total charges is the same for both the reactants and the products.

Name two metallic oxides which dissolve in water.

Sodium oxide ( Na 2 O ) and potassium oxide ( K 2 O ) are two metal oxides that dissolve in water. Calcium oxide is also a metallic oxide which dissolve in water. Sodium oxide reacts with water to form sodium hydroxide which is a strong alkali. Similarly, potassium oxide reacts with water to form potassium hydroxide, and calcium oxide reacts with water to form calcium hydroxide.