1. 1.5 M
2. 1.66 M
3. 0.017 M
4. 1.59 M
The mass percent of carbon in carbon dioxide is:
1. | 0.034% | 2. | 27.27% |
3. | 3.4% | 4. | 28.7% |
The incorrect statement among the following is:
1. | A molecule of a compound has atoms of different elements. |
2. | A compound cannot be separated into its constituent elements by the physical method of separation. |
3. | A compound retains the physical properties of its constituent elements. |
4. | The ratio of atoms of different elements in a compound is fixed. |
Which of the following statements is correct about the reaction is given below?
1. | Total mass of iron and oxygen in reactants = total mass of iron and oxygen in product therefore it follows law of conservation of mass |
2. | Total mass of reactants = total mass of product, therefore, law of multiple proportions is followed |
3. | Amount of Fe2O3 can be increased by taking any one of the reactants (iron or oxygen) in excess. |
4. | Amount of Fe2O3 produced will decrease if the amount of any one of the reactants (iron or oxygen) is taken in excess. |
Identify the reaction that does not obey the law of conservation of mass from the provided options:
1.
2.
3.
4.
Which of the following statement indicates that the law of multiple proportions is being followed?
1. | A sample of carbon dioxide taken from any source will always have carbon and oxygen in the ratio of 1:2. |
2. | Carbon forms two oxides namely, CO2 and CO, where masses of oxygen that combine with a fixed mass of carbon are in the simple ratio of 2:1. |
3. | When magnesium burns in oxygen, the amount of magnesium used for the reaction is equal to the amount of magnesium formed in magnesium oxide. |
4. | At constant temperature and pressure, 200 mL of hydrogen will combine with 100 mL of oxygen to produce 200 mL of water vapour. |
Match the following:
Column-I | Column-II | ||
A. | 88 g of CO2 | 1. | 0.25 mol |
B. | 6.022×1023 molecules of H2O | 2. | 2 mol |
C. | 5.6 L of O2 at STP | 3. | 3 mol |
D. | 96 g of O2 | 4. | 1 mol |
A | B | C | D | |
1. | 2 | 4 | 1 | 3 |
2. | 1 | 2 | 3 | 4 |
3. | 1 | 4 | 3 | 2 |
4. | 4 | 1 | 3 | 2 |
Match the following physical quantities with units.
Physical quantity | Unit | ||
A. | Molarity | 1. | mol kg–1 |
B. | Molality | 2. | mol L–1 |
C. | Pressure | 3. | Candela |
D. | Luminous intensity | 4. | Pascal |
Codes:
A | B | C | D | |
1. | 1 | 4 | 2 | 3 |
2. | 2 | 1 | 4 | 3 |
3. | 1 | 4 | 3 | 2 |
4. | 4 | 1 | 3 | 2 |
Assertion (A): | The empirical mass of ethene is half of its molecular mass. |
Reason (R): | The empirical formula represents the simplest whole-number ratio of the various atoms present in a compound. |
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. |