p-Block

Question 1

What orbitals are involved in the pi orbitals in NO3-, PO4(3-)?

Answer 1

p. spd

Question 2

Borax and kernite difference? Where does borax occur?

Answer 2

10H2O vs 4H2O. Puga Valley (Ladakh), Sambhar Lake (Rajasthan)

Question 3

Half life of nihonium?

Answer 3

20 seconds

Question 4

g13 radius order?

Order of electronegativity?

Answer 4

B < Ga < Al < In < Tl

Decreases from B to Al, then increases marginally

Question 5

Why is gallium useful for measuring high temperature?

Answer 5

High boiling point

Question 6

Why only p orbitals involved in bonding for higher elements?

Answer 6

inert pair effect

Question 7

Enaught value for Al3+/Al

Tl3+/Tl

Answer 7

-1.66

+1.26

Question 8

White fumes appear around the bottle of
anhydrous aluminium chloride. Give
reason.

Answer 8

HCl

Question 9

Borax contains tetranuclear units?

Answer 9

Na2[B4O5(OH)4]- (learn the structure)

Question 10

Banana bond angles?

Answer 10

97 and 120

Question 11

Heat resistant glasses made of boron?

Answer 11

Pyrex

Question 12

Conductivity of aluminum is ______ that of copper

Answer 12

twice

Question 13

Half year of C14?

Answer 13

5770 years

Question 14

The electronegativity from Si to Pb

Answer 14

almost the same

Question 15

Sn in +2 state is a

Answer 15

reducing agent

Question 16

Only acidic monoxide? Only g14 element to react with water?

Answer 16

GeO. Tin

Question 17

SnF4 and PbF4, which are ______ in nature

Answer 17

ionic

Question 18

Why B mostly covalent

Answer 18

High ionization enthalpy

Question 19

Lewis acid behaviour ___________ in trivalent state as we go down

Answer 19

decreases

Question 20

Why BCl3 doesn’t dimerize?

Answer 20

B can’t accomodate 4 Cl

Question 21

AlCl3 dimer bond angle order?

Bond length order?

Answer 21

Cl-Al-Cl (outer) > Al-Cl-Al > Cl- Al - Cl (inner)

terminal bond smaller

Question 22

Al is passive to which acid

Answer 22

conc HNO3

Question 23

no. of sp3 and sp2 in
1. borax
2. boric acid

Answer 23

1. 2 sp3, 2 sp2

2. sp2

Question 24

NABH4 + I2 gives?

Answer 24

diborane

Question 25

B2H6 forms adducts with?

Answer 25

NMe3, CO

Question 26

CO is a _____________ agent

Answer 26

reducing