Assertion (A): | Melting point of gallium is lesser than aluminum. |
Reason (R): | Due to the inert pair effect, increased effective nuclear charge holds ns-electrons tightly. |
1. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
3. | (A) is True but (R) is False. |
4. | (A) is False but (R) is True. |
Statement I: | Gallium (Ga) has a low melting point, so it is used in thermometers. |
Statement II: | A substance having a melting point of 253 K can be measured by a Gallium thermometer. |
1. | Statement I is false but Statement II is true. |
2. | Both Statement I and Statement II are false. |
3. | Both Statement I and Statement II are true. |
4. | Statement I is true but Statement II is false. |
The protective film of oxide on the surface of Al metal may be strengthened by:
(1) galvanizing
(2) cathodizing
(3) sheradizing
(4) anodizing
a. | \(B_2H_6 \) is Lewis acid. |
b. | \(B_2H_6 \) has a planar structure. |
c. | \(B_2H_6 \). | All B-H Bond lengths are equal in
d. | \(B_2H_6,\) four \(3C-2e^- \) bonds are present. | In
e. | \(B_2H_6 \) can be prepared by the reaction of \(BF_3 \) and \(NaBH_4 \). |
1. | a, b, c, d, e | 2. | a, e |
3. | a, b | 4. | d, e |
Given below are two statements:
Assertion (A): | Boric acid is considered a weak acid. |
Reason (R): | Boric acid is not able to release H+ ions on its own. |
1. | Both (A) and (R) are true and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are true but (R) is not the correct explanation of (A). |
3. | (A) is true but (R) is false. |
4. | (A) is false but (R) is true. |
Boric acid on heating at gives
1.
2.
3.
4.
Assertion (A): | Sn4+ ion is more stable than Sn+2. |
Reason (R): | The inert pair effect dominates down the groups. |
1. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
3. | (A) is True but (R) is False. |
4. | (A) is False but (R) is True. |
Statement I: | In group 14, a significant increase in covalent radius is observed from carbon to silicon and thereafter, a small increase in covalent radius is observed from silicon to germanium. |
Statement II: | A considerable difference in the values of electronegativity from silicon to lead is observed. |
1. | Both Statement I and Statement II are correct. |
2. | Both Statement I and Statement II are incorrect. |
3. | Statement I is correct but Statement II is incorrect. |
4. | Statement I is incorrect but Statement II is correct. |
The best reducing agent is
1.
2.
3.
4.