CBSE
Which of the following element is a metalloid?
Bi
Sn
Ge
C
KI and CusO4 solution when mixed, give :
CuI2 + K2SO4
Cu2I2 + K2SO4
K2SO4 + Cu2I2 + I2
K2SO4 + CuI2 + I2
The metal used to recover copper from a solution of CuSO4 is :
Fe
He
Na
Ag
Which of the following elements never show positive oxidation number?
O
Fe
Ga
F
Which among the following elements have lowest value of IE1?
Pb
Sn
Si
C
The correct order of radii is
N <Be <B
F-<O2-<N3-
Na< Li< K
Fe3+< Fe2+< Fe4+
Which of the following element shows maximum valency ?
Carbon
Barium
Nitrogen
Sulphur
What is the name of element with atomic number 105?
Kurchatovium
Dubnium
Nobelium
Holmium