CBSE
How many neutrons are present in tritium nucleus?
2
3
1
0
Alums are used for
tanning of leather
coagulation of blood
purification of water
all of the above
The ortho and para hydrogen differ in respect of which of the following ?
In the molecular weight
In the nature of spin of protons
In the nature of spin of electrons
In the number of protons
Which gas is evolved by the treatment of magnesium with very dilute solution of HNO3?
N2
NO2
H2
H2O
Water gas is :
CO + N2
CO + CO2 + CH4
CO2 + N2
CO + H2
Permanent hardness can be removed by adding
Cl2
Na2CO3
Ca(OCl)Cl
K2CO3
The method used to remove temporary hardness of water is :
Clark's method
Ion-exchange method
Synthetic resins method
Calgon's method
The high boiling point of water is due to which reason:
co-ordinate bonding
covalent bond
electrostatic force of attraction
hydrogen bonding