Question

Please help me with 17 & 18!!
Thankss in advance!! :) ​

Answer 1

#17

#a

Group 15 elements have valency 3

• B,Al are the answers

#b

• Oxygen is more reactive

Let's check the EC of both

`\\ \rm\Rrightarrow [O]=1s^22s^22p^4`

`\\ \rm\Rrightarrow [S]=[Ne]3s^23p^4`

• Oxygen is smaller in size
• Hence more electronegative.

#c

Decrease in size

• Farther we go in a period more electrons are added to the atom .So nuclear charge increases and atomic radius decreases

#18

#a

• HNO_3

#b

• Nitric acid is a acid so methyl orange turns red

#c

• Used as oxidising agent