Question

Using Crisscross method,write down the formulaes of following

(a)Sodiumoxide

(b)Calciumcarbonate​

Answer 1

Explanation:

a) $Na^{+1}$ + $O^{-2}$

if you crisscross the +1 will go to oxygen and the -2 will go to sodium

=$Na_{2} O$

b) $Ca^{+2}$   $CO_3^{-2}$

if you crisscross the +2 will go to carbonate and -2 will go to calcium

= $Ca_{2}(CO_3)_2$