Which of the following has highest hydration energy?
MgCl2
CaCl2
BaCl2
SrCl2
A.
MgCl2
Smaller sized and highly charged ions have higher hydration energy. In the alkaline earth metals, the hydration energy of the compact ions is greater than the large sized ions. Therefore, order of hydration energy in this group is
Be2+ > Mg2+ > Ca2+ > Sr2+ > Ba2+.
Which of the following reactions produces hydrogen?
Mg + H2O
H2S2O8 + H2O
BaO2 + HCl
Na2O2 + 2HCl
Assertion : BeSO4 is soluble in water while BasO4 is not.
Reason : Hydration energy decreases down the group from Be to Ba and lattice energy remains almost constant.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false
If both assertion and reason are false.
The first ionisation enthalpy of Na, Mg and Si are 496, 737, 776 kJ/mol respectively. What will be the first ionisation enthalpy potential of Al in kJ/mol?
> 766 kJ/ mol
> 496 and < 737 kJ
>737 and < 766 kJ/mol
>496 kJ/mol
When NaCl is dissolved in water , the sodium ions becomes :
oxidised
reduced
hydrolysed
hydrated
The temporary hardness of water due to calcium bicarbonate can be removed by adding :
CaCO3
Ca(OH)2
CaCl2
HCl
The compound which does not exist as hydrate form
ferrous sulphate
copper sulphate
magnesium sulphate
sodium chloride
Which of the following acids will not evolve H2 gas on reaction with alkali metals?
Hydrazoic acid
Perxenic acid
Boric acid
None of these