#Chemistry #JEE #NEET
1. The compound which does not possess a peroxide linkage is :
a. Na2O2 b. CrO3 c. H2SO3 d. PbO2
2. Soldiers of Napolean army while at Alps during bb freezing winter suffered a serious problem as regards to the tin buttons of their uniforms.White metallic tin button got converted into grey powder.This transformation is related to :
a. A change in the partial pressure of oxygen in air.
b. A change inn the crystalline structure of tin.
c. An interaction with nitrogen of air at very low
d. An interaction with water vapour contained in humid air.
3. Which one of the following statements about
zeolites is false:
A.zeolite are alumina silicates having 3D network.
b. Some of SiO44- units are replaced by AlO43- & AlO69-ions in zeolite.
c. They are used as cation exchangers.
d. They have open structure which enables them to take up small molecules.
4. Which of the following acts as UV rays :
a. soda glass b. Crook’s glass c. Pyrex d. none
5. The stability of dihalides of Si,Ge,Sn,Pb increases
steadily in sequence :
a. GeX2 < SiX2 < SnX2 <PbX2
b.. SiX2 < PbX2 < SnX2 < GeX2
c.. SiX2 < GeX2 < SnX2 < PbX2
d.PbX2 < SnX2 < GeX2 < SiX2
6. Sodium oxalate on heating with conc. H2SO4 gives :
a. CO only b. CO2 only
c. CO & CO2 d. SO2 & SO3
7. Glass reacts with HF to produce :
a. SiF4 b. H2SiF6 c. H2SiO3 d. Na3AlF6
8. Extraction of lead by reduction methods done by :
a.adding more galena into reverbaratory furnace
b. adding more lead sulphate to reverbaratory
c. adding more galena & coke into reverbaratory
d. self reduction of oxide form sulphide present in
9. Which is used to produce smoke screen :
a. calcium phosphide b. zinc sulphide
c. sodium carbonate d. zinc phosphide
10. When tin is treated with conc. nitric acid ,
a. it is converted into stannous nitrate.
b. it is converted into stannic nitrate
c. it is converted into metastannic acid.
d. it becomes passive.
Answer : 1.d 2.b 3.b 4.b 5.c 6.c 7.b 8.a 9.a 10.c