Assertion (A): | H2O is the only hydride of the chalcogen family that is liquid. |
Reason (R): | The acidic nature of hydrides of the chalcogen family increases down the group. |
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. | Both (A) and (R) are false. |
Assertion (A): | PF5 and IF3 have similar shapes. |
Reason (R): | All the bond lengths are equal in PF5. |
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. | Both (A) and (R) are false. |
Assertion (A): | The atomic size of F is smaller than that of Cl. |
Reason (R): | F-F bond is stronger than the Cl-Cl bond. |
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. |
Assertion (A): | Noble gases have the highest ionization energies in their respective periods. |
Reason (R): | The outermost sub-shell of noble gases in which the electron enters is completely filled. |
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. | Both (A) and (R) are false. |
Assertion (A): | The valency and oxidation number of sulphur in S8 respectively are 2 and 0. |
Reason (R): | S8 Rhombic is the most stable allotropic form of sulphur. |
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. | Both (A) and (R) are false. |
Assertion (A): | SF6 cannot be hydrolysed but SF4 can be. |
Reason (R): | Six F-atoms in SF6 prevent the attack of H2O on sulphur atom of SF6 |
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. |
Assertion (A): | NaCl reacts with concentrated H2SO4 to give colourless fumes with a pungent smell. But on adding MnO2, the fumes become greenish-yellow |
Reason (R): | MnO2 oxidizes HCl to chlorine gas which is greenish-yellow. |
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. |
Assertion (A): | Both rhombic and monoclinic sulphur exist as S8 but oxygen exists as O2. |
Reason (R): | Oxygen forms pπ - pπ multiple bonds due to its small size and small bond length but pπ - pπ bonding is not possible in sulphur. |
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. | Both (A) and (R) are false. |
Assertion (A): | HI cannot be prepared by the reaction of KI with concentrated H2SO4. |
Reason (R): | HI has the lowest H—X bond strength among halogen acids. |
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. |
Given below are two statements:
Assertion (A): | HNO3 makes iron passive. |
Reason (R): | HNO3 forms a protective layer of ferric nitrate on the surface of the iron. |
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. |