315733
Which of the following does not illustrate the anomalous properties of \(\mathrm{Li}\) ?
1 The m.p. and b.p. of Li are comparatively high
2 Li forms a nitride \(\mathrm{Li}_{3} \mathrm{~N}\) unlike other alkali metals
3 \(\mathrm{Li}\) is much softer than the other alkali metals
4 \(\mathrm{Li}^{+}\)ion and its compounds are more heavily hydrated than those of the rest of the group.
Explanation:
Amongst the alkali metals, Li has the smallest size and strong metallic bonding. Therefore, it is much harder than the other group 1 metals.
CHXI10:THE S-BLOCK ELEMENTS
315734
Assertion : \(\mathrm{LiCl}\) is predominantly a covalent compound. Reason : Electronegativity difference between \(\mathrm{Li}\) and \(\mathrm{Cl}\) is too small.
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
Explanation:
Assertion is correct. Small size of \(\mathrm{Li}^{+}\) makes it highly polarising, introduces predominant covalency in \(\mathrm{LiCl}\). Reason is wrong, there is very large difference in electronegativity of \(\mathrm{Li}\) and \(\mathrm{Cl}\).
CHXI10:THE S-BLOCK ELEMENTS
315735
The melting point of lithium \(\left(181^{\circ} \mathrm{C}\right)\) is just double the melting point of sodium \(\left(98^{\circ} \mathrm{C}\right)\) because
1 down the group, the hydration energy decreases
2 down the group, the ionization energy decreases
3 down the group the cohesive energy decreases
4 none of these
Explanation:
The atom becomes larger on descending the group, so the bonds becomes weaker (metallic bond), the cohesive force/energy decreases and accordingly melting point also decreases.
CHXI10:THE S-BLOCK ELEMENTS
315736
Li has the maximum value of ionisation potential among alkali metals i.e. lithium has the minimum tendency to ionise to give \(\mathrm{Li}^{+}\)ion. Lithium is
1 Strongest reducing agent
2 Poorest reducing agent
3 Strongest oxidising agent
4 Poorest oxidising agent
Explanation:
The ionisation potential value of Lithium is maximum among alkali metals i.e., its tendency to ionise to give \(\mathrm{Li}^{+}\)ions should be the minimum i.e. \({\text{Li}}\) should be the poorest reducing agent. But, lithium is the strongest reducing agent. This is due to the largest value of hydration energy of \(\mathrm{Li}^{+}\)ions.
CHXI10:THE S-BLOCK ELEMENTS
315737
Lithium is the only alkali metal which is not placed in kerosene but is wrapped in paraffin wax, because
1 It reacts with kerosene
2 In floats to the surface of kerosene because of low density
3 It does not react with air and \(\mathrm{H}_{2} \mathrm{O}\)
315733
Which of the following does not illustrate the anomalous properties of \(\mathrm{Li}\) ?
1 The m.p. and b.p. of Li are comparatively high
2 Li forms a nitride \(\mathrm{Li}_{3} \mathrm{~N}\) unlike other alkali metals
3 \(\mathrm{Li}\) is much softer than the other alkali metals
4 \(\mathrm{Li}^{+}\)ion and its compounds are more heavily hydrated than those of the rest of the group.
Explanation:
Amongst the alkali metals, Li has the smallest size and strong metallic bonding. Therefore, it is much harder than the other group 1 metals.
CHXI10:THE S-BLOCK ELEMENTS
315734
Assertion : \(\mathrm{LiCl}\) is predominantly a covalent compound. Reason : Electronegativity difference between \(\mathrm{Li}\) and \(\mathrm{Cl}\) is too small.
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
Explanation:
Assertion is correct. Small size of \(\mathrm{Li}^{+}\) makes it highly polarising, introduces predominant covalency in \(\mathrm{LiCl}\). Reason is wrong, there is very large difference in electronegativity of \(\mathrm{Li}\) and \(\mathrm{Cl}\).
CHXI10:THE S-BLOCK ELEMENTS
315735
The melting point of lithium \(\left(181^{\circ} \mathrm{C}\right)\) is just double the melting point of sodium \(\left(98^{\circ} \mathrm{C}\right)\) because
1 down the group, the hydration energy decreases
2 down the group, the ionization energy decreases
3 down the group the cohesive energy decreases
4 none of these
Explanation:
The atom becomes larger on descending the group, so the bonds becomes weaker (metallic bond), the cohesive force/energy decreases and accordingly melting point also decreases.
CHXI10:THE S-BLOCK ELEMENTS
315736
Li has the maximum value of ionisation potential among alkali metals i.e. lithium has the minimum tendency to ionise to give \(\mathrm{Li}^{+}\)ion. Lithium is
1 Strongest reducing agent
2 Poorest reducing agent
3 Strongest oxidising agent
4 Poorest oxidising agent
Explanation:
The ionisation potential value of Lithium is maximum among alkali metals i.e., its tendency to ionise to give \(\mathrm{Li}^{+}\)ions should be the minimum i.e. \({\text{Li}}\) should be the poorest reducing agent. But, lithium is the strongest reducing agent. This is due to the largest value of hydration energy of \(\mathrm{Li}^{+}\)ions.
CHXI10:THE S-BLOCK ELEMENTS
315737
Lithium is the only alkali metal which is not placed in kerosene but is wrapped in paraffin wax, because
1 It reacts with kerosene
2 In floats to the surface of kerosene because of low density
3 It does not react with air and \(\mathrm{H}_{2} \mathrm{O}\)
315733
Which of the following does not illustrate the anomalous properties of \(\mathrm{Li}\) ?
1 The m.p. and b.p. of Li are comparatively high
2 Li forms a nitride \(\mathrm{Li}_{3} \mathrm{~N}\) unlike other alkali metals
3 \(\mathrm{Li}\) is much softer than the other alkali metals
4 \(\mathrm{Li}^{+}\)ion and its compounds are more heavily hydrated than those of the rest of the group.
Explanation:
Amongst the alkali metals, Li has the smallest size and strong metallic bonding. Therefore, it is much harder than the other group 1 metals.
CHXI10:THE S-BLOCK ELEMENTS
315734
Assertion : \(\mathrm{LiCl}\) is predominantly a covalent compound. Reason : Electronegativity difference between \(\mathrm{Li}\) and \(\mathrm{Cl}\) is too small.
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
Explanation:
Assertion is correct. Small size of \(\mathrm{Li}^{+}\) makes it highly polarising, introduces predominant covalency in \(\mathrm{LiCl}\). Reason is wrong, there is very large difference in electronegativity of \(\mathrm{Li}\) and \(\mathrm{Cl}\).
CHXI10:THE S-BLOCK ELEMENTS
315735
The melting point of lithium \(\left(181^{\circ} \mathrm{C}\right)\) is just double the melting point of sodium \(\left(98^{\circ} \mathrm{C}\right)\) because
1 down the group, the hydration energy decreases
2 down the group, the ionization energy decreases
3 down the group the cohesive energy decreases
4 none of these
Explanation:
The atom becomes larger on descending the group, so the bonds becomes weaker (metallic bond), the cohesive force/energy decreases and accordingly melting point also decreases.
CHXI10:THE S-BLOCK ELEMENTS
315736
Li has the maximum value of ionisation potential among alkali metals i.e. lithium has the minimum tendency to ionise to give \(\mathrm{Li}^{+}\)ion. Lithium is
1 Strongest reducing agent
2 Poorest reducing agent
3 Strongest oxidising agent
4 Poorest oxidising agent
Explanation:
The ionisation potential value of Lithium is maximum among alkali metals i.e., its tendency to ionise to give \(\mathrm{Li}^{+}\)ions should be the minimum i.e. \({\text{Li}}\) should be the poorest reducing agent. But, lithium is the strongest reducing agent. This is due to the largest value of hydration energy of \(\mathrm{Li}^{+}\)ions.
CHXI10:THE S-BLOCK ELEMENTS
315737
Lithium is the only alkali metal which is not placed in kerosene but is wrapped in paraffin wax, because
1 It reacts with kerosene
2 In floats to the surface of kerosene because of low density
3 It does not react with air and \(\mathrm{H}_{2} \mathrm{O}\)
315733
Which of the following does not illustrate the anomalous properties of \(\mathrm{Li}\) ?
1 The m.p. and b.p. of Li are comparatively high
2 Li forms a nitride \(\mathrm{Li}_{3} \mathrm{~N}\) unlike other alkali metals
3 \(\mathrm{Li}\) is much softer than the other alkali metals
4 \(\mathrm{Li}^{+}\)ion and its compounds are more heavily hydrated than those of the rest of the group.
Explanation:
Amongst the alkali metals, Li has the smallest size and strong metallic bonding. Therefore, it is much harder than the other group 1 metals.
CHXI10:THE S-BLOCK ELEMENTS
315734
Assertion : \(\mathrm{LiCl}\) is predominantly a covalent compound. Reason : Electronegativity difference between \(\mathrm{Li}\) and \(\mathrm{Cl}\) is too small.
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
Explanation:
Assertion is correct. Small size of \(\mathrm{Li}^{+}\) makes it highly polarising, introduces predominant covalency in \(\mathrm{LiCl}\). Reason is wrong, there is very large difference in electronegativity of \(\mathrm{Li}\) and \(\mathrm{Cl}\).
CHXI10:THE S-BLOCK ELEMENTS
315735
The melting point of lithium \(\left(181^{\circ} \mathrm{C}\right)\) is just double the melting point of sodium \(\left(98^{\circ} \mathrm{C}\right)\) because
1 down the group, the hydration energy decreases
2 down the group, the ionization energy decreases
3 down the group the cohesive energy decreases
4 none of these
Explanation:
The atom becomes larger on descending the group, so the bonds becomes weaker (metallic bond), the cohesive force/energy decreases and accordingly melting point also decreases.
CHXI10:THE S-BLOCK ELEMENTS
315736
Li has the maximum value of ionisation potential among alkali metals i.e. lithium has the minimum tendency to ionise to give \(\mathrm{Li}^{+}\)ion. Lithium is
1 Strongest reducing agent
2 Poorest reducing agent
3 Strongest oxidising agent
4 Poorest oxidising agent
Explanation:
The ionisation potential value of Lithium is maximum among alkali metals i.e., its tendency to ionise to give \(\mathrm{Li}^{+}\)ions should be the minimum i.e. \({\text{Li}}\) should be the poorest reducing agent. But, lithium is the strongest reducing agent. This is due to the largest value of hydration energy of \(\mathrm{Li}^{+}\)ions.
CHXI10:THE S-BLOCK ELEMENTS
315737
Lithium is the only alkali metal which is not placed in kerosene but is wrapped in paraffin wax, because
1 It reacts with kerosene
2 In floats to the surface of kerosene because of low density
3 It does not react with air and \(\mathrm{H}_{2} \mathrm{O}\)
315733
Which of the following does not illustrate the anomalous properties of \(\mathrm{Li}\) ?
1 The m.p. and b.p. of Li are comparatively high
2 Li forms a nitride \(\mathrm{Li}_{3} \mathrm{~N}\) unlike other alkali metals
3 \(\mathrm{Li}\) is much softer than the other alkali metals
4 \(\mathrm{Li}^{+}\)ion and its compounds are more heavily hydrated than those of the rest of the group.
Explanation:
Amongst the alkali metals, Li has the smallest size and strong metallic bonding. Therefore, it is much harder than the other group 1 metals.
CHXI10:THE S-BLOCK ELEMENTS
315734
Assertion : \(\mathrm{LiCl}\) is predominantly a covalent compound. Reason : Electronegativity difference between \(\mathrm{Li}\) and \(\mathrm{Cl}\) is too small.
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but reason is correct.
Explanation:
Assertion is correct. Small size of \(\mathrm{Li}^{+}\) makes it highly polarising, introduces predominant covalency in \(\mathrm{LiCl}\). Reason is wrong, there is very large difference in electronegativity of \(\mathrm{Li}\) and \(\mathrm{Cl}\).
CHXI10:THE S-BLOCK ELEMENTS
315735
The melting point of lithium \(\left(181^{\circ} \mathrm{C}\right)\) is just double the melting point of sodium \(\left(98^{\circ} \mathrm{C}\right)\) because
1 down the group, the hydration energy decreases
2 down the group, the ionization energy decreases
3 down the group the cohesive energy decreases
4 none of these
Explanation:
The atom becomes larger on descending the group, so the bonds becomes weaker (metallic bond), the cohesive force/energy decreases and accordingly melting point also decreases.
CHXI10:THE S-BLOCK ELEMENTS
315736
Li has the maximum value of ionisation potential among alkali metals i.e. lithium has the minimum tendency to ionise to give \(\mathrm{Li}^{+}\)ion. Lithium is
1 Strongest reducing agent
2 Poorest reducing agent
3 Strongest oxidising agent
4 Poorest oxidising agent
Explanation:
The ionisation potential value of Lithium is maximum among alkali metals i.e., its tendency to ionise to give \(\mathrm{Li}^{+}\)ions should be the minimum i.e. \({\text{Li}}\) should be the poorest reducing agent. But, lithium is the strongest reducing agent. This is due to the largest value of hydration energy of \(\mathrm{Li}^{+}\)ions.
CHXI10:THE S-BLOCK ELEMENTS
315737
Lithium is the only alkali metal which is not placed in kerosene but is wrapped in paraffin wax, because
1 It reacts with kerosene
2 In floats to the surface of kerosene because of low density
3 It does not react with air and \(\mathrm{H}_{2} \mathrm{O}\)
