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What is the equivalent weight of SnCl₂ in the following reaction;

SnCl2 + Cl2 → SnCl4 A. 95 B. 45 C. 60 D. 30 Solution: (A) SnCl2 + Cl2 → SnCl4 Equivalent weight of SnCl2 = mol.wt. / 2 =... View Article

Camphor is often used in molecular mass determination because;

A. It is readily available B. It has a very high cryoscopic constant C. It is volatile D. It is solvent for organic substances Solution:... View Article

Of two oxides of iron, the first contained 22% and the second contained 30% of oxygen by weight. The ratio of weights of iron in the two oxides that combine with the same weight of oxygen is;

A. 3:2 B. 2:1 C. 1:2 D. 1:1 Solution: (A) For first oxide, Moles of oxygen = 22 / 16 = 1.375, Moles of Fe = 78 / 56 = 1.392... View Article

An alkaloid contains 17.28 % of nitrogen and its molecular mass is 162. The number of nitrogen atoms present in one molecule of the alkaloid is;

A. Five B. Four C. Three D. Two Solution: (D) Amount of nitrogen present in one mole of alkaloid i.e., in 162g = 162 × 17.28 /... View Article

The percentage of element M is 53 in its oxide of molecular formula M₂O₃. Its atomic mass is about;

A. 45 B. 9 C. 18 D. 36 E. 27 Solution: (E) Let us assume the atomic mass of M = x Therefore, molecular weight of compound = 2x + 16... View Article

The equivalent weight of KMnO4 for acid solution is;

A. 79 B. 31.6 C. 52.16 D. 158 Solution: (B) An equivalent weight of a solution is defined as the molecular weight of the solute divided... View Article

If the molecular wt. of Na₂S₂O₃ and I₂ are M₁ and M₂ respectively, then what will be the equivalent wt. of Na₂S₂O₃ and I₂ in the following reaction?

A. M1, M2 B. M1, M2 / 2 C. 2M1, M2 D. M1, 2M2 Solution: (B) ∴ Equivalent mass of S2O2−3 = M1 / 1 = M1 Equivalent mass of... View Article

2gm of metal carbonate is neutralized completely by 100 mL of 0.1(N)HCl. The equivalent weight of metal carbonate is;

A. 50 B. 100 C. 150 D. 200 Solution: (D) As 2g of metal carbonate is neutralised by 100mL of 0.1NHCl. ∵ Number of gram-equivalents of... View Article

A compound has the molecular formula, X₄O₆. If 10 g of X4O6 has 5.72 g X , then calculate atomic mass of X.

A. 32 u B. 64 u C. 67 u D. 98 u Solution: (A) Molecular weight of X4O6 = (4a + 96) As such, (4a + 96)g X4O6 contains X = 4a g... View Article

0.56 g of gas occupies 280cm3 at NTP. Then its molecular mass is:

A. 4.8 B. 44.8 C. 11.2 D. 22.4 Solution: (B) At NTP, 280 cc or 0.28 L weigh 0.56 g of a gas. Since we know that, 22.4 L corresponds... View Article

Number of atoms in 560 g Fe (atomic mass 56 g mol^-1) is:

A. Twice that of 70 g N B. Half that of 20 g H C. Both A and B D. None of the above Solution: (C) Let N be Avogadro's number. The... View Article

Total number of atoms in 44g of CO₂ is;

A. 6.02 × 1023 B. 6.02 × 1024 C. 1.806 × 1024 D. 18.06 × 1022 Solution: (A) Molecular mass in gms = 6.02... View Article

How many moles of Al2(SO4)3 would be in 50g of the substance?

A. 0.0843 mol B. 0.952 mol C. 0.481 mol D. 0.140 mol Solution: (D) Number of moles = Mass / Molecular mass Given, mass of Al2(SO4)3 =... View Article

A signature written with carbon pencil weighs 1 mg. What is the number of carbon atoms present in the signature?

A. 6.02 × 1020 B. 0.502 × 1020 C. 5.02 × 1023 D. 5.02 × 1020 Solution: (B) 1 mg = 1 × 10−3 g 12... View Article

The mass of one mole of electron is;

A. 9.1 × 10−28 g B. 0.55 mg C. 9.1 × 10−24 g D. 6 × 10−12 g Solution: (B) We know, Mass of 1... View Article

Calculate the total number of protons in 10g of calcium carbonate is (N0 = 6.023 × 1023):

A. 3.01×1024 B. 4.06×1024 C. 2.01×1024 D. 3.02×1024 Solution: (A) 1 mole of CaCO3 = 20 × 1 + 6 × 1... View Article

How many moles of magnesium phosphate, Mg₃(PO₄)₂ will contain 0.25 mole of oxygen atoms?

A. 0.02 B. 3.125 x 10-2 C. 1.25 x 10-2 D. 2.5 x 10-2 Solution: (B) In one molecule of magnesium phosphate, 8 oxygen atoms are present.... View Article

The value of amu is which of the following?

A. 1.57 × 10−24 kg B. 1.66 × 10−24 kg C. 1.99 × 10−23 kg D. 1.66 × 10−27 kg Solution: (D)... 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:

Assertion: Equal moles of different substances contain the same number of constituent particles. Reason: Equal weights of different substances... View Article

Law of constant composition is same as the law of:

A. Conservation of mass B. Conversation of energy C. Multiple proportion D. Definite proportion Solution: (D) Law of definite... View Article