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Gram molecular volume of oxygen at STP is;

A. 3200 cm3 B. 5600 cm3 C. 22400 cm3 D. 11200 cm3 Solution: (C) Gram Molecular volume is the volume occupied by 1 mole of molecules and... View Article

Which one of the following has maximum number of oxygen atoms?

A. 2 g of water B. 2 g of sulphur dioxide C. 2 g of carbon dioxide D. 2 g of carbon monoxide Solution: (A) Number of atoms present in... View Article

The number of gram molecules of chlorine in 6.02×1025 hydrogen chloride molecules is;

A. 5 B. 50 C. 100 D. 10 Solution: (C) 1 Mole of HCl = 1 + 35.5 = 36.5 = 6.023 × 1023 Number of gram molecules = 6.02 ×... View Article

Number of atoms of He in 100u of He (atomic wt of He is 4) are;

A. 25 B. 100 C. 50 D. 100 × 6 × 10−23 Solution: (A) No.ofatoms= Mass of substance / Atomic mass = 100 / 4 = 25 Atoms... View Article

0.1 mole of a carbohydrate with empirical formula CH₂O contains 1g of hydrogen. What is its molecular formula?

A. C5H10O5 B. C6H12O6 C. C4H8O4 D. C3H6O3 Solution: (A) Let molecular formula be (CH2O)n In one mole of carbohydrate, hydrogen... View Article

80g of oxygen contains as many atoms as in;

A. 80g of hydrogen B. 1g of hydrogen C. 10g of hydrogen D. 5g of hydrogen Solution: (D) Oxygen atom contains 16 g of oxygen 80g of... View Article

Mass of 0.1mole of methane is;

A. 1g B. 16g C. 1.6g D. 0.1g Solution: (C) Mass of one mole of methane (CH4) = 16g Mass of 0.1 mole of methane = 16 × 0.1g = 1.6g.... View Article

The number of formula units of calcium fluoride, CaF₂ present in 146.4g of CaF₂ (the molar mass of CaF₂ is 78.08g/mol) is.

A. 1.129 × 1024CaF2 B. 1.146 × 1024CaF2 C. 7.808 × 1024CaF2 D. 1.877 × 1024CaF2 Solution: (A) CaF2 = 146.4g... View Article

What will 1 mole of CO₂ contain?

A. 6.023 x 1023 atoms of C B. 6.023 x 1023 atoms of O C. 18.1 x 1023 molecules of CO2 D. 3g atoms of CO2 Solution: (A) One mole of CO2... View Article

Arrange the following in the order of increasing mass (atomic mass O = 16, Cu = 63, N = 14)

I. One atom of oxygen II. One atom of nitrogen III. 1×10−10 mole of oxygen IV. 1×10−10 mole of copper A. II <... View Article

The total number of electrons present in 18 ml of water is:

A. 6.023 × 10−24 B. 6.023 × 1024 C. 6.023 × 1023 D. 12.023 × 1024 Solution: () The total number of... View Article

Which one of the following set of units represents the smallest and largest amount of energy respectively?

A. J and erg B. erg and cal C. cal and eV D. L−atm and J E. eV and L−atm Solution: (E) Smallest and largest amount of... View Article

The percentage weight of Zn in white vitriol [ZnSO₄.7H₂O] is approximately equal to (at.mass of Zn = 65, S = 32, 0 = 16 and H = 1)

A. 33.65 % B. 32.56 % C. 23.65 % D. 22.65 % Solution: (D) Molecular weight of white vitriol [ZnSO4.7H2O] = 65 + 32 + (4 × 16) +... View Article

In the following questions, two statements are given, one is Assertion (A) and the other is Reason (R). Examine the statements carefully and mark the correct answer according to the instructions given below:

A: The standard unit for expressing atomic mass is amu. R: Now a days amu is represented by ‘u’. A. If both A and R are correct... View Article

In the following questions, two statements are given, one is Assertion (A) and the other is Reason (R). Examine the statements carefully and mark the correct answer according to the instructions given below:

A: 1 L of O2 and 1 L of O3 contains the same number of moles under identical conditions. R: Under identical conditions, 1 L of O2 and 1 L of O3... View Article

In the following questions, two statements are given, one is Assertion (A) and the other is Reason (R). Examine the statements carefully and mark the correct answer according to the instructions given below:

A: Cinnabar is a chemical compound whereas brass is a mixture. R: Cinnabar always contain 6.25 times more mercury than sulphur by weight. Brass... View Article

In the following questions, two statements are given, one is Assertion (A) and the other is Reason (R). Examine the statements carefully and mark the correct answer according to the instructions given below:

A: The mass of the products formed in a reaction depends upon the limiting reactant. R: Limiting reactant reacts completely in the reaction.... View Article

In the following questions, two statements are given, one is Assertion (A) and the other is Reason (R). Examine the statements carefully and mark the correct answer according to the instructions given below:

A: Mass numbers of most of the elements are fractional. R: Mass numbers are obtained by comparing with the mass number of carbon taken as 12.... View Article

In the following questions, two statements are given, one is Assertion (A) and the other is Reason (R). Examine the statements carefully and mark the correct answer according to the instructions given below:

A: Pure water, irrespective of its source always contain hydrogen and oxygen in the ratio of 1:8 by mass. R: Total mass of reactants and... View Article

In the following questions, two statements are given, one is Assertion (A) and the other is Reason (R). Examine the statements carefully and mark the correct answer according to the instructions given below:

A: Atomic mass of sodium is 23 u. R: An atom of sodium is 23 times heavier than an atom of 12C. A. If both A and R are correct and R is the... View Article