Q. No.If the speed of light is 3.0 × 108 m s–1, then the distance covered by light in 2.00 nanoseconds will be -
1. 0.500 m
2. 0.600 m
3. 0.700 m
4. 0.800 m
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
15.15 pm in the basic unit will be
1. 1.515 × 10–12 m
2. 2.57 × 10–11 m
3. 2.87 × 10–11 m
4. 1.515 × 10–11 m
Which will have the largest number of atoms among the following?
1. 1 g Au (s)
2. 1 g Na (s)
3. 1 g Li (s)
4. 1 g of Cl2(g)
What would be the molarity of a solution of ethanol in water if the mole fraction of ethanol is 0.040?
(assume the density of water to be 1)
1. 3.143 M
2. 2.314 M
3. 2.413 M
4. 2.141 M
The mass of one 12C atom in g is:
1. 1.393 x 10-23
2. 1.993 x 10-23
3. 1.773 x 10-23
4. 1.593 x 10-23
The number of significant figures present in the answer of the following calculations [(i), (ii), (iii)] are respectively -
| 1. | 0 . 02856 × 298 . 15 × 0 . 112 / 5785 |
| 2. | 5 × 5.364 |
| 3. | 0.0125 + 0.7864 + 0.0215 |
| 1. | 4, 4, 3 | 2. | 3, 3, 4 |
| 3. | 4, 3, 4 | 4. | 3, 4, 4 |
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 |
The highest number of atoms is present in -
1. 52 moles of Ar
2. 52 u of He
3. 52 g of He.
4. All of the above have the same number of atoms
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