Q. No.
10 g of a silver coin, when dissolved completely in excess of conc. HNO3 gives 8.5 g of silver nitrate.
The percentage purity of the coin is:
(Molar mass of silver is 108g)
1.
25%
2.
54%
3.
67%
4.
100%
The percentage purity of the coin is:
(Molar mass of silver is 108g)
| Assertion (A): | 1 a.m.u = 1 .66 × 10−24 gram. |
| Reason (R): | The actual mass of one atom of C-12 is equal to 1.99 × 10-23 g. |
| 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): | The number of molecules in 2 moles of NH3 is equal to the number of molecules in 4 moles of CH4. |
| Reason (R): | Both are chemically similar species. |
| 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): | When 4 moles of H2 reacts with 2 moles of O2, then 4 moles of water are formed. |
| Reason (R): | O2 will act as a limiting reagent. |
| 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. |
Calculate the mass percentages of sodium (Na), sulfur (S), and oxygen (O), respectively, in sodium sulfate (Na₂SO₄).
1. 32.4%, 45.05% and 22.6%
2. 22.6%, 45.05% and 32.4%
3. 32.4%, 22.6% and 45.05%
4. 45.05%, 32.4% and 22.6%
In a reaction A + B2 → AB2,
A will act as a limiting reagent if :
| i. | 300 atoms of A reacts with 200 molecules of B |
| ii. | 2 moles A reacts with 3 moles B2 |
| iii. | 100 atoms of A reacts with 100 molecules of B |
| iv. | 5 moles A reacts with 2.5 moles B |
| v. | 2.5 moles A reacts with 5 moles B2 |
Choose the correct option:
| 1. | (i), (ii) | 2. | (i), (ii), (v) |
| 3. | (ii), (v) | 4. | All |
If 10 volumes of H2 gas react with 5 volumes of O2 gas, the volumes of water vapor produced would be:
1. 9
2. 8
3. 10
4. 11
The molar mass of naturally occurring Argon isotopes is:
| Isotope | Isotopic molar mass | Abundance |
| 36-Ar | 35.96755 g mol–1 | 0.337% |
| 38-Ar | 37.96272 g mol–1 | 0.063% |
| 40-Ar | 39.9624 g mol–1 | 99.600% |
| 1. | 49.99947 g mol-1 | 2. | 39.99947 g mol-1 |
| 3. | 35.59947 g mol-1 | 4. | 45.59947 g mol-1 |
How many grams of HCl are required to react with 5.0 g of manganese dioxide in the reaction provided?
\(4 \mathrm{HCl}_{(\mathrm{aq})}+\mathrm{MnO}_{2(\mathrm{~s})} \rightarrow 2 \mathrm{H}_2 \mathrm{O}_{(\mathrm{l})}+\mathrm{MnCl}_{2(\mathrm{aq})}+\mathrm{Cl}_{2(\mathrm{~g})}\)
1. 4.8 g
2. 6.4 g
3. 2.8 g
4. 8.4 g
| List I | List II | ||
| a. | Micro | i. | m |
| b. | Mega | ii. | m |
| c. | Giga | iii. | m |
| d. | Femto | iv. | m |
| a | b | c | d | |
| 1. | i | iv | iii | ii |
| 2. | iii | iv | ii | i |
| 3. | ii | iii | iv | i |
| 4. | i | iii | iv | ii |
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