Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
JEE Main201912 Apr 2019Morning ShiftChemistrySome Basic Concepts of ChemistryActual

5 moles of A B 2 weigh 125 × 10 - 3 k g and 10 moles of A 2 B 2 weigh 300 × 10 - 3 k g . The molar mass of A ( M A ) in k g m o l - 1 are:

Options

  1. AM A = 5 × 10 - 3 and M B = 10 × 10 - 3
  2. BM A = 25 × 10 - 3 and M B = 50 × 10 - 3
  3. CM A = 50 × 10 - 3 and M B = 25 × 10 - 3
  4. DM A = 10 × 10 - 3 and M B = 5 × 10 - 3

Correct answer

A. M A = 5 × 10 - 3 and M B = 10 × 10 - 3

Step-by-step solution

Mass of 1 mole of A B 2 = 125 × 10 - 3 k g 5 = 125   g m 5 = 25   g m Similarly, mass of 1 mole of A 2 B 2 = 300 × 10 - 3 k g 10 = 30   g m Let molar mass of A   is x and B is y

Practice Some Basic Concepts of Chemistry on Quantrex Academy →

More from Some Basic Concepts of Chemistry

Match List-I with List-II. List-I Mass of substance List-II Number of atoms A. 1.8 mg water I. 2 10⁻⁴ N_A B. 9.8 mg sulphuric acid II. 1.5 10⁻⁴ N_A C. 1.8 mg carbon III. 3 10⁻⁴ N_A 2026Which of the following contain the same number of atoms ? (Given : Molar mass in g mol ⁻¹ of H, He, O and S are 1, 4, 16 and 32 respectively) A. 2 g of O₂ gas B. 4 g of SO₂ gas C. 2026An oxide of iron contains 69.9 % iron, its empirical formula, is: (Given: Molar mass of Fe and O are 56 and 16 g mol ⁻¹ respectively.) 2026What volume of hydrogen gas at STP would be liberated by action of 50 mL of H₂SO₄ of 50 % purity (density = 1.3 g mL ⁻¹ ) on 20 g of zinc ? Given : Molar mass of H, O, S, Zn are 1, 2026How many grams of residue is obtained by heating 2.76 g of silver carbonate? (Given: Molar mass of C, O and Ag are 12 , 16 and 108 g mol ⁻¹ respectively) 2026The correct order of total number of atoms present in (A) 2 moles of cyclohexane (B) 684 g of sucrose (C) 90.8 L of dihydrogen at STP is: 2026Number of moles and number of molecules in 1.4187 L of SO₂ at STP respectively are: 2026The ratio of mass percentage (w/w) of C : H in a hydrocarbon is 12 : 1 . It has two carbon atoms. The weight (in g) of CO₂(g) formed when 3.38 g of this hydrocarbon is completely b 2026 Full Some Basic Concepts of Chemistry list All JEE Main PYQs