An element E combines with O2 to form an oxide E2O


#1

An element E combines with O2 to form an oxide E2O, which is a good conductor of electricity. Answer the following:
(i) How many electrons will be present in the outermost shell of E?
(ii) Write the formula of the compound formed when it combines with chlorine.


#2

(i) Valency of the element E is (+) 1. This means that it has only one electron in the valence shell.
(ii)

Valency of Cl is (-) 1 and while that of E is (+) 1. Therefore, the formula will be ECl.