By which method the molecular mass of benzene was determined as 78.108 ?
(A) Specific gravity method
(B) Vapour density method
(C) X-ray diffraction method
(D) Distillation methos
Nitration of chlorobenzene gives___________________?
(A) o – chloronitrobenzene
(B) p – chloronitrobenzene
(C) m – chloronitrobenzene
(D) A & B
Because of its ability to combine with both oxygen and nitrogen aluminium metal is used_____________?
(A) As nitrometer
(B) To remove air bubbles from molten metal
(C) To produce alloy
(D) As insulator
Orthoboric acid is 2.6% soluble in water at 40?C and ___________at 107°C.
(A) 26%
(B) 27%
(C) 37%
(D) <2.6%
In network of silica (SiO2) each silicon atom is surrounded by _____________ atoms of osygen?
(A) 4
(B) 2
(C) 1
(D) 6
Which electronic configuration corresponds to an element of group IIIA ?
(A) 1s2 2s2 2p3
(B) 1s2 2s2 2p6 3s2 3p1
(C) 1s2 2s2 2p4
(D) 1s2 2s2 2p6 3s2 3p6 4s2 3d1
Aluminium oxide is_________________?
(A) Acidic oxide
(B) Basic oxide
(C) Amphoteric oxide
(D) It does not exists
Special features of borate glass is that it is_________________?
(A) Heat resistant
(B) Low melting
(C) Used to prepare chemical garden
(D) Green in colour
Borax is a white crystalline solid and it is_________________?
(A) More soluble in cold water
(B) More soluble in hot water
(C) Insoluble in water
(D) Soluble only in organic solvents
One of the outstanding features of boron is its ability to form__________________?
(A) Molecular addition compounds
(B) Molecular crystals
(C) Semiconductors
(D) Ionic compounds