The common oxidation state of lanthanides is_________?
A. +3
B. +2
C. +1
D. +4
Submitted by :- Jamil Ahmed
Which one of the following is a bridge element?
Which group contains elements that exist as monoatomic molecule?
A. 1
B. 2
C. 14
D. 18
Submitted by :- Jamil Ahmed
The law of traids is applicable to__________?
A. Li, Be, B
B. F, Cl, Br
C. Cl, Br, I
D. Na, K, Rb
Submitted by :- Jamil Ahmed
Grignard reagent gives carboxylic acid with____________?
The Latin word formica means ant. The name formic acid is derived from this Latin word because__________?
A. this acid, in ancient times, was used to eliminate ant-hills
B. this corrosive acid is secreted by ants to drive away their enemies
C. this acid was first obtained by the distillation of ants
D. ants are attracted by the odor of this acid
Submitted by :- Jamil Ahmed
What is the structure of IF7 ?
| A) Triagonal bipyramid | B) Pentagonal bipyramid |
| C) Square pyramid | D) tetrahedral |
Submitted by :- Muhammad Nawaz
The octane number of zero is assigned to____________?
A. 2-methyl octane
B. n-heptane
C. iso-octane
D. 3-methyl octane
Submitted by :- Jamil Ahmed
The heat required to raise the temperature of body by 1 K is called___________?
A. specific heat
B. thermal capacity
C. water equivalent
D. None of the above
Submitted by :- Jamil Ahmed
Brass gets discoloured in air because of the presence of which of the following gases in air ?
| A) Hydrogen sulphide | B) Oxygen |
| C) Nitrogen | D) Carbon dioxide |
Submitted by :- Muhammad Nawaz