Assertion (A): Irrespective of the source, a given compound always contains the
same elements in the same proportion.
Reason (R): This law is referred to as the law of multiple proportions.
 
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.
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Consider the given two statements:
Statement I: The law of multiple proportions is followed by the gases SO2 and SO3, but not by CO and CO2.
Statement II:  Dalton’s theory explains the laws of chemical combination as well as laws of gaseous volumes.
Select the correct option:
1.  Statement I is correct, and Statement II is correct.
2.  Statement I is incorrect, and Statement II is correct.
3.  Statement I is correct, and Statement II is incorrect.
4.  Statement I is incorrect, and Statement II is incorrect.
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At constant T and P, 5.0 L of SO2 is reacted with 3.0 L of O2 according to the following equation:

2SO2(g)   +   O2(g)   →   2SO3(g)

The volume of the remaining reaction mixture at the completion of the reaction will be:

1. 0.5 L

2. 8.0 L

3. 5.5 L

4. 5 L

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Consider the given two statements:
Statement I: 1 amu is defined as the mass exactly equal to one-twelfth of the mass of one carbon-12 atom.
Statement II: Number of atoms in 8 u of He is 2NA.
In the light of above statements, choose the correct option from the following :
1.  Both Statement I and Statement II are correct.
2.  Both Statement I and Statement II are incorrect.
3.  Statement I is correct but Statement II is incorrect.
4.  Statement I is incorrect but Statement II is correct
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The vapour density of a mixture containing \(NO_{2}\) and \(N_{2} O_{4}\)  is 38.3. The mole of \(NO_{2}\) in a 100 g mixture is:

[Vapour density = (Molar mass / 2)]

1. 0.437

2. 0.347

3. 0.557

4. 0.663

Subtopic:  Introduction |
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What will be the mass of one atom of \(^{12}C\)?
1. 1 a.m.u.
2. \(1.9923\times10^{-23}~\text{g}\)
3. \(1.6603\times10^{-22}~\text{g}\)
4. 6 a.m.u.
Subtopic:  Moles, Atoms & Electrons | Introduction |
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What is the total volume of gases present after the completion of the reaction between 150 cm3 of F2 and 100 cm3 of Cl2​​​​​​?
3F2 (g) + Cl 2(g) → 2ClF3 (g)
(assuming the reaction occurs at constant temperature and pressure)

1. 250 cm3
2. 150 cm3
3. 350 cm3
4. 200 cm3
Subtopic:  Limiting Reagent | Introduction |
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