(A) Bromine
(B) Nitrogen
(C) Chlorine
(D) Phosphorous
The percentage value of O2 by weight in atmosphere is?
(A) 47%
(B) 86%
(C) 78%
(D) 21%
Extremely used metal is?
(A) Iron
(B) Cesium
(C) Lead
(D) Silver
The density of O2 gas at 20 Degree Centigrade is?
(A) 1.4 gdm-3
(B) 1.5 gcm-3
(C) 1.8 gdm-3
(D) 1.0 gdm-3
Number of elements in fourth period is?
(A) 6
(B) 18
(C) 32
(D) 23
Atomic number of Aluminium is?
(A) 10
(B) 11
(C) 12
(D) 13
The lustrous non metal is?
(A) Carbon
(B) Sulphur
(C) Phosphorus
(D) Iodine
Oxidation number of Hydrogen in HCL is?
(A) -1
(B) +1
(C) 0
(D) -2