chemistry

Question 1

Which EX3 is not stable?

Answer 1

NX3 (But NF3 is stable)

Question 2

Which EX3 halides are covalent?

Answer 2

All except BiF3

Question 3

Does NX5 exist?

Answer 3

No, coz N doesn’t have vacant d orbitals

Question 4

What method of preparation gives pure N2?

Answer 4

Thermal decomposition of sodium and barium azide

Question 5

Nitrolim (Fertilizer)

Answer 5

CaCN2+C

Question 6

Catalyst used in Haber process? Now VS earlier

Answer 6

Now: Fe along with Al2O3 and K2O

Earlier: Fe along with Mo as promoter

Question 7

Brown Ring test

Answer 7

Nitrate salt + FeSO4 + conc. H2SO4.

Brown ring formed due to: [Fe(H2O)5(NO)]

Question 8

Bauxite

Answer 8

Al2O3.2H2O

Question 9

Pyrolusite

Answer 9

MnO2 (black)

Question 10

Haematite

Answer 10

Fe2O3

Question 11

Cassiterite

Answer 11

SnO2

Question 12

Which element is found in hair as keratin

Answer 12

sulphur

Question 13

Gypsum

Answer 13

CaSO4.2H2O

Question 14

Baryte

Answer 14

BaSO4

Question 15

Epsom salt

Answer 15

MgSO4.7H2O

Question 15

Galena
Cinnabar
Zinc blende
Copper Pyrites
Copper glance
Silver Glance

Answer 15

PbS
HgS
ZnS
CuFeS2
Cu2S
Ag2S

Question 16

Which member of chalcogens family doesnt show allotropy?

Answer 16

All of them do

Question 16

Decay product of Thorium and Uranium

Answer 16

Po

Question 16

MP and BP order of chalcogens

Answer 16

O<S<Se<Po<Te