Q. No.What is the term used to define the temperature at which the solid and liquid phases of a pure substance can exist in equilibrium at a particular temperature and atmospheric pressure?
(a) Normal melting point
(b) Equilibrium temperature
(c) Boiling point
(d) Freezing point
Choose the correct option:
| 1. | (a, b) | 2. | (b, c) |
| 3. | (c, d) | 4. | (a, d) |
For the reaction N2O4(g) ⇌ 2NO2(g), the value of K(equilibrium constant) is 50 at 400 K and 1700 at 500 K. Which of the following option(s) is/are correct?
| (a) | The reaction is endothermic. |
| (b) | The reaction is exothermic. |
| (c) | If NO2(g) and N2O4(g) are mixed at 400 K at partial pressures 20 bar and 2 bar respectively, more N2O4(g) will be formed. |
| (d) | The entropy of the system increases. |
1. (a, b, d)
2. (b, c, d)
3. (b, d, a)
4. (a, c, d)
Given below are two statements:
| Assertion (A): | In the dissociation of PCl5 at constant pressure and temperature, the addition of helium at equilibrium increases the dissociation of PCl5. |
| Reason (R): | Helium reacts with Cl2 . |
| 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): | An aqueous solution of ammonium acetate can act as a buffer. |
| Reason (R): | Acetic acid is a weak acid and NH4OH is a weak base. |
| 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): | An aqueous solution of ammonium carbonate is basic. |
| Reason (R): |
The acidic or basic nature of a salt solution of a salt of a weak acid and a weak base depends on the Ka and Kb values of the acid and the base forming it. |
| 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): | For any chemical reaction at a particular temperature, the equilibrium constant is fixed and is a characteristic property. |
| Reason (R): | Equilibrium constant is independent of temperature. |
| 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): | The ionisation of hydrogen sulphide in water is low in the presence of hydrochloric acid. |
| Reason (R): | Hydrogen sulphide is a weak acid. |
| 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): | A solution containing a mixture of acetic acid and sodium acetate maintains a constant value of pH on the addition of small amounts of acid or alkali. |
| Reason (R): | A solution containing a mixture of acetic acid and sodium acetate acts as a buffer solution. |
| 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): | The increasing order or acidity of hydrogen halides is HF<HCI<HBr<HI. |
| Reason (R): | While comparing acids formed by the elements belonging to the same group of the periodic table, H-A bond strength is a more important factor in determining the acidity of an acid than the polar nature of the 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. |
Match Column-I with Column-II and mark the appropriate option:
|
Column-I (Term) |
Column-II (Conditions) |
||
| (A) |
Equilibrium |
(i) | |
| (B) |
Spontaneous reaction |
(ii) | |
| (C) |
Non-spontaneous reaction |
(iii) |
Codes:
| Options: | A | B | C |
| 1. | (ii) | (iii) | (i) |
| 2. | (i) | (ii) | (iii) |
| 3. | (ii) | (i) | (iii) |
| 4. | (iii) | (i) | (ii) |
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