The p-Block Elements - Online Test
Q1.
The valence shell electronic configuration of p-block elements is ns2np1-6. But this is not true in the case of
Answer : Option B
Explaination / Solution:
He has configuration. It is a noble gas.
Q2. There are six groups of p-block elements in the periodic table numbering from
Answer : Option C
Explaination / Solution:
After two s block and 10 d block, p block elements starts from group 13 to group 18.
Q3. The variation in properties in a group of p-block of elements is due to
Answer : Option C
Explaination / Solution:
The difference in properties of p block element is because of presence of inner lying d and f electrons which have poor shielding effect.
Q4. The maximum oxidation state shown by any p-block element is
Answer : Option D
Explaination / Solution:
Maximum oxidation state of any p block element is the number of ionisable electrons which is equal to the sum of s and p electrons present in valence shell. For example valance shell electronic configuration of group 15 element is so max oxidation state is +5
Q5. The sum of the s and p-electrons is called
Answer : Option D
Explaination / Solution:
Group oxidation state is the highest oxidation state exhibited by the elements present in any particular group.
For p block elements it is the sum of the s and p-electrons.
Q6. Inert pair effect of p-block elements is due to the
Answer : Option D
Explaination / Solution:
The inert pair effect is nothing but the extra stability concept. Generally P-block elements shows variable valiancy which is equal to the maximum oxidation (Group oxidation state) state of that group of p-block elements, p block elements may show other oxidation state i.e.+2.
Group oxidation state +4 is obtained when electrons are lost from both ns and np levels,
+2 oxidation state is obtained while only np level electrons are lost due to extra stability and poor shielding of ns electron which are called inert pair. The effect is the inert effect
Q7. Among the following which is the strongest oxidizing agent?
Answer : Option D
Explaination / Solution:
Because of its highest electronegativity it (F2) is very strongest oxidizing agent.
Q8. As we move from B to Al in the p-block elements the sum of the first three ionisation enthalpies
Answer : Option A
Explaination / Solution:
On moving from B to Al size of the atom increases. So ionisation enthalpy decreases. Thus as we move from B to Al in the p-block elements the sum of the first three ionisation enthalpies considerably decreases.
This is the reason aluminium forms Al3+ ion.
This is the reason aluminium forms Al3+ ion.
Q9. Boron forms only covalent compounds and not +3 ions because
Answer : Option C
Explaination / Solution:
Due to smaller size and high nuclear charge B has very high ionization energy value so does not show +3 oxidation state.
Further according to Fajan's rule, cation with small size and high positive charge leads to covalent bond.
Q10. One of the following p-block elements has unusually low melting point
Answer : Option B
Explaination / Solution:
Ga does not do not follow any of the simple crystal structures. And two nearest Ga atoms are bonded by covalent bond which leads to low melting point.
