Which of the following alkaline earth metal sulphates has hydration enthalpy higher than the lattice enthalpy?
A
CaSO4
B
BeSO4
C
BaSO4
D
SrSO4
Explanation
The hydration enthalpy of BeSO4
is higher
than its lattice energy. Within group 2, the hydration
energy decreases down the group while lattice
energy is almost the same.
2
MCQ (Single Correct Answer)
AIPMT 2010 Prelims
Property of the alkaline earth metals that increases with their atomic number
A
solubility of their hydroxides in water
B
solubility of their sulphates in water
C
ionization energy
D
electronegativity
Explanation
On moving down the group, basic nature of
these hydroxides increases due to low ionization
enthalpies because M-O bond in MOH is weak and
thus break to give OH– ions in the solution.
3
MCQ (Single Correct Answer)
AIPMT 2009
Which of the following oxides is not expected to react with sodium hydroxide?
A
CaO
B
SiO2
C
BeO
D
B2O3
Explanation
NaOH is a strong alkali. It combines with
acidic and amphoteric oxides to form salts. Since
CaO is a basic oxide hence does not reacts with
NaOH.
4
MCQ (Single Correct Answer)
AIPMT 2009
In the case of alkali metals, the covalent character decreases in the order
A
MF > MCl > MBr > MI
B
MF > MCl > MI > MBr
C
MI > MBr > MCl > MF
D
MCl > MI > MBr > MF
Explanation
According to Fajans’ rule,
Covalent character $$ \propto $$ size of anion $$ \propto $$
1
size of cation
.
Now the order of size of anions in the given options
is as follows
F–
< Cl–
< Br–
< I–
Thus, the covalent character of the given
compounds varies as
MI > MBr > MCl > MF
Questions Asked from s-Block Elements
On those following papers in MCQ (Single Correct Answer) Number in Brackets after Paper Name Indicates No of Questions