Q. No.One mole of carbon atom weights 12 g, the number of atoms in it is equal to:
(Mass of carbon – 12 is )
1.
2.
3.
4.
(Mass of carbon – 12 is )
| 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. |
From 440 mg of CO2, 1021 molecules are removed. The moles of CO2 remaining is:
1. 8.34 X 10-3
2. 0.88 x 10-3
3. 8. 45 X 10-2
4. 8.81 X 103
Percentage of C, H & N in a compound is given as follows:
C=40%; H=13.33%; N=46.67%
The empirical formula of the compound will be:
1.
2.
3.
4.
The percentages of C, H, and N in an organic compound are 40%, 13.3%, and 46.7% respectively.
The empirical formula of the compound is:
| 1. | C3H13N3 | 2. | CH2N |
| 3. | CH4N | 4. | CH6N |
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
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