# 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.

Subtopic:  Empirical & Molecular Formula |
72%
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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.
Subtopic:  Moles, Atoms & Electrons |
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 Assertion (A): The significant figure for 0.200 is 3, whereas the significant figure for 200 is 1. Reason (R): Zero at the end or right of a number is significant, provided it is not on the right side 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 (A) is false but (R) is true.

Subtopic:  Introduction |
56%
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 Assertion (A): The combustion of 16 g of methane gives 18 g of water. Reason (R): In the combustion of methane, water is one of the products.

 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.
Subtopic:  Moles, Atoms & Electrons |
66%
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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
Subtopic:  Introduction |
94%
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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
Codes
 A B C D 1. 2 4 1 3 2. 1 2 3 4 3. 1 4 3 2 4. 4 1 3 2
Subtopic:  Moles, Atoms & Electrons |
92%
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 Assertion (A): 1 a.m.u = 1 .66 × 10−24 gram . Reason (R): The actual mass of one atom of C-12 is equal to 1.99 × 10-23 g .

 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.
Subtopic:  Moles, Atoms & Electrons |
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 Assertion (A): The number of molecules in 2 moles of NH3 is equal to the number of molecules in 4 moles of CH4. Reason (R): Both are chemically similar species.
 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.
Subtopic:  Moles, Atoms & Electrons |
81%
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 Assertion (A): When 4 moles of H2 reacts with 2 moles of O2, then 4 moles of water are formed. Reason (R): O2 will act as a limiting reagent.

 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.

Subtopic:  Equation Based Problem |
57%
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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 not related to this statement?

(a) Law of conservation of mass

(b) Law of definite proportions

(c) Law of multiple proportions

1. (a), (d)

2. (b), (c)

3. (c), (d)

4. (b), (d)

Subtopic:  Introduction |
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