Question

An element X combines with hydrogen to form a compound XH₃. The element Xis placed on the right side of the periodic table. Which of the following statement is correct for element X? 

I. Has two valence electrons. 

II. Is a metal and is solid. 

III. Is a non-metal and is a gas. 

IV. Has five valence electrons. 

V. XH₃ reacts with water to forma basic compound. 

A. I, H and III 

B. II, III and IV 

C. III, IV and V 

D. V, I and II

Answer 1

The element X is nitrogen which reacts with hydrogen to form NH₃. Nitrogen is a non-metal and a gas. It has 5 valence electrons (electronic configuration:2,5) and reacts with water to form ammonium hydroxide (NH₄OH) which is basic in nature.