Pure silicon doped with phosphorus is a
metallic conductor
insulator
n-type semiconductor
p-type semiconductor
IUPAC name of the following compound
N, N- dimethylcyclopropane carboxamide
N-methylcyclopropanamide
cyclopropionamide
None of the above
Sodium formate on heating gives
oxalic acid and H2
sodium oxalate and H2
sodium oxalate
CO2 and caustic soda
Which does not give a precipitate with AgNO3 solution?
[Co(NH3)6]Cl3
[Co(NH3)5Cl]Cl2
[Co(NH3)4Cl2]Cl
[Co(NH3)3Cl3]
Total volume of atoms present in a face centred cubic unit cell of a metal is (r is atomic radius)
Gold number is associated with
amount of gold
protective colloids
purple of cassius
electrophoresis
A.
amount of gold
The protective power of a colloid is expressed as gold number. Gold number is defined as the minimum amount of lyophilic colloid in milligrams which prevents the flocculation of 10 ml gold sol by the addition of 1 ml of 10% NaCl solution.
Noble gases are used in discharge tubes to give different colours. Reddish-orange glow is due to
Ar
Ne
Xe
Kr