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 react completely with 5 volumes of O₂, what volume of water vapor will be produced under the same conditions of temperature and pressure?
1. 9
2. 8
3. 10
4. 11
Find the value of 15.15 pm expressed in the basic SI unit of length.
1. 1.515 × 10–12
2. 2.57 × 10–11 m
3. 2.87 × 10–11 m
4. 1.515 × 10–11 m
Determine the number of significant figures that should be present in the final answers for each of the following expressions:
| I. | 0.02856 × 298.15 × 0.112 / 5785 |
| II. | 5 × 5.364 |
| III. | 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 |
Find the mass of CaCO₃ required to completely react with 25 mL of 0.75 M HCl according to the reaction:
CaCO₃(s) + 2HCl(aq) → CaCl₂(aq) + CO₂(g) + H₂O(l)
1. 0.36 g
2. 0.09 g
3. 0.96 g
4. 0.66 g
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 |
The numbers 234,000 and 6.0012 can be represented in scientific notation as:
| 1. | \(2.34 \times 10^{-9} \text { and } 6 \times 10^3\) |
| 2. | \(0.234 \times 10^{-6} \text { and } 60012 \times 10^{-9}\) |
| 3. | \(2.34 \times 10^{-9} \text { and } 6.0012 \times 10^{-9}\) |
| 4. | \(2.34 \times 10^5 \text { and } 6.0012 \times 10^0\) |