Question

(I) Explain why hydrogen is not placed with the halogen in the periodic table. 

(II) Complete the following reactions.

Al₄ C₃ + D₂O → ? 

CaC₂ + D₂O → ? 

Mg₃N₂ , + D₂O → ? 

Ca₃P₂ + D₂O → ?

Answer 1

(I) 

1. Hydrogen resembles alkali metals as well as halogens. 

2. Hydrogen resembles more alkali metals than halogens.

3. Electron affinity of hydrogen is much less than that of halogen atom. Hence the tendency to form hydride ion is low compared to that of halogens. 

4. In most of its compounds hydrogen exists in +1 oxidation state. Therefore it is reasonable to place the hydrogen in group 1 along with alkali metals as shown in the latest periodic table published by IUPAC.

(II)