Q. No.
A mixture of and gas "Y" (mol. wt. 80) in the mole ratio a : b has a mean molecular weight of 40. What would be the mean molecular weight, if the gases are mixed in the ratio b : a under identical conditions? (assume that these gases do not react)
| 1. | 40 | 2. | 48 |
| 3. | 62 | 4. | 72 |
What is the correct ascending order of masses for the following (I to IV)?
(Atomic mass : N=14, O=16 Cu = 63)
I. 1 molecule of oxygen
II. 1 atom of nitrogen
III. 1 x 10-10g molecule-weight of oxygen
IV. 1 x 10-10g atom-weight of copper
Codes
1. II < I < III < IV
2. IV < III < II < I
3. II < III < I < IV
4. III < IV < I < II
| Assertion (A): | 1 g O2 and 1 g O3 have an equal number of oxygen atoms. |
| Reason (R): | O2 and O3 have different molar masses. |
| 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. |
The molecular formula of a commercial resin used for exchanging ions in water softening is . The maximum uptake of ions by the resin when expressed in mole per gram resin is:
\( \mathrm{C}_8 \mathrm{H}_7 \mathrm{SO}_3 \mathrm{Na}+\mathrm{Ca}^{2+} \rightarrow (\mathrm{C}_8 \mathrm{H}_7 \mathrm{SO}_{3}){_2} \mathrm{Ca}+ \mathrm{Na}^{+}\)
1.
2.
3.
4.
The average molar mass of the mixture of and present in the mole ratio of a:b is
20 g mol-1. When the mole ratio is reversed, the molar mass of the mixture will be:
| 1. | 24 gram | 2. | 42 gram |
| 3. | 20 gram | 4. | 15 gram |
| 1. | \(1~ a.m.u.\) | 2. | \(1.9923\times10^{-23}~\text{g}\) |
| 3. | \(1.6603\times10^{-22}~\text{g}\) | 4. | \(6~ a.m.u.\) |
The specific volume of cylindrical virus particle is hose radius and length are 7 Å & 10Å respectively. If \(\text{mol}^{-1}\), find the molecular weight.
1. \( 15.4 \mathrm{~kg} / \mathrm{mol} \)
2. \(1.54 \times 10^4 \mathrm{~kg} / \mathrm{mol} \)
3. \( 3.08 \times 10^4 \mathrm{~kg} / \mathrm{mol}\)
4. \(3.08 \times 10^3 \mathrm{~kg} / \mathrm{mol}\)
| 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. |
Given below are two statements:
| Assertion (A): | One atomic mass unit is defined as one-twelfth of the mass of one carbon-12 atom. |
| Reason (R): | The carbon-12 isotope is the most abundant isotope of carbon and has been chosen as the standard. |
| 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. |
The number of gram molecules of oxygen in 6.02 × 1024 CO molecules are:
1. 10 g molecules
2. 5 g molecules
3. 1 g molecules
4. 0.5 g molecules
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