Use Mendeléev’s Periodic Table to predict the formulae for the oxides of the following elements:
K, C, AI, Si, Ba.

Explanation

(i) The element K is in group I of Mendeleev.s Periodic Table in which the general formula of the oxides of elements is `R_2O`, therefore, the formula of oxide of K will be `K_2O`.
(ii) The element C is in group IV of Mendeleev.s periodic table in which the general formula of the oxides of elements is `RO_2`, therefore, the formula of oxide of C will be `CO_2`.
(iii) The element Al is in group III of Mendeleev.s Periodic Table in which the general formula of the oxides of elements is `R_2O_3` , therefore, the formula of oxide of Al will be `Al_2O_3`
(iv) The element Si is in group IV of Mendeleev.s Periodic Table in which the general formula of the oxides of elements is `RO_2`, therefore, the formula of oxide of Si will be `SiO_2`.
(v) The element Ba is in group II of Mendeleev.s Periodic Table in which the general formula of the oxides of elements is RO, therefore, the formula of oxide of Ba will be BaO .