An element B show valencies of 4 and 6. Write the formulae of its two oxides.

An element X shows two valencies i.e. 2 and 4. Write the formula of its oxides.

An element X shows two valencies of 3 and 5. Work out the formulae of two oxides of this element.

An element Z has valency of 3. Write down the formula of its oxide?

An element Y has a valancy of 4. Write the formula for its carbonate

The valency of an element A is 4. Write the formula of its oxide.

(a) Write the symbols/formulae of two simple ions and two compound ions (or polyatomic ions). (b) An element Y has a valency of 4. Write the formula for its : (i) Chloride , (ii) oxide , (iii) sulphate, (iv) carbonate , (v) nitrate

An element X shows a variable valency of 3 and 5. What are the formulae of the oxide formed by it?

An element has valency 3. Write the formula of its oxide.