Q. No.| Column I (Prefixes) |
Column II (Multiples) |
||
| (A) | pico | (i) | \(10^9\) |
| (B) | femto | (ii) | \(10^{-3}\) |
| (C) | milli | (iii) | \(10^{-12}\) |
| (D) | giga | (iv) | \(10^{-15}\) |
1. (A) →(i), (B)→(ii), (C) →(iii), (D)→ (iv)
2. (A) →(ii), (B)→(i), (C) →(iv), (D)→ (iii)
3. (A) →(iv), (B)→(iii), (C) →(i), (D)→ (ii)
4. (A) →(iii), (B)→(iv), (C) →(ii), (D)→ (i)
One of the statements of Dalton's atomic theory is given below:
"Compounds are formed when atoms of different elements combine in a fixed ratio."
Which of the following laws is/are related to this statement?
1. Law of conservation of mass
2. Law of definite proportions
3. Law of reciprocal proportions
4. Avogadro's law
The approximate hydrogen-to-oxygen ratio of 1:8 in water samples from seas, rivers, or lakes illustrates the law of:
| 1. | Multiple proportions | 2. | Definite proportion |
| 3. | Reciprocal proportions | 4. | None of the above |
1. 40%
2. 50%
3. 67%
4. 75%
1. 100 has four significant figures
2. \(1.00\times 10^2\) has four significant figures
3. 2.005 has four significant figures
4. 0.0025 has four significant figures
A jug contains 2L of milk. The volume of the milk in m3 is:
1. 2 × 10–3
2. 2 × 104
3. 2 × 102
4. 2 × 105
| Assertion (A): | The number 0.200 has 3 significant figures, while 200 has only 1 significant figure. |
| Reason (R): | Zeros at the end of a number are considered significant only if they are to the right of the decimal point. |
| 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. |
1. H2O and H2O2
2. H2O and D2O
3. NaCl and NaBr
4. MgO and Mg(OH)2
Carbon (C) and Oxygen (O) combine to form two compounds, carbon monoxide (CO) and carbon dioxide (CO₂). The masses of oxygen that combine with a fixed mass of carbon are in the ratio 16 : 32.
Based on this information, identify the correct statement(s):
| a. | The compounds illustrate the Law of Multiple Proportions. |
| b. | The mass ratio of oxygen in the two compounds is 1:2. |
| c. | The fixed mass of carbon in both compounds is 12 g. |
| d. | The compounds violate the Law of Definite Proportions. |
Choose the correct answer among the following options:
2. Only a, c, and d
3. Only b, c, and d
4. Only b and c
© 2026 GoodEd Technologies Pvt. Ltd.