JEE Mains · Chemistry · STD 11 - 1. Some basic concept of chemistry

Match List-I with List-II.
List-I
Mass of substance List-II
Number of atoms
A. \(1.8\) mg water I. \(2\times 10^{-4}\times N_A\)
B. \(9.8\) mg sulphuric acid II. \(1.5\times 10^{-4}\times N_A\)
C. \(1.8\) mg carbon III. \(3\times 10^{-4}\times N_A\)
D. \(5.85\) mg salt (NaCl) IV. \(7\times 10^{-4}\times N_A\)
Choose the correct answer from the options given below:

List-I Mass of substance	List-II Number of atoms
A. \(1.8\) mg water	I. \(2\times 10^{-4}\times N_A\)
B. \(9.8\) mg sulphuric acid	II. \(1.5\times 10^{-4}\times N_A\)
C. \(1.8\) mg carbon	III. \(3\times 10^{-4}\times N_A\)
D. \(5.85\) mg salt (NaCl)	IV. \(7\times 10^{-4}\times N_A\)

A A-IV, B-III, C-I, D-II
B A-III, B-II, C-IV, D-I
C A-III, B-IV, C-II, D-I
D A-III, B-IV, C-I, D-II

Verified Solution

Answer & Solution

Correct Answer

(C) A-III, B-IV, C-II, D-I

Step-by-step Solution

Detailed explanation

For A: Molar mass of \(H_2O = 18\) g/mol. Moles of \(H_2O = \dfrac{1.8 \times 10^{-3}}{18} = 10^{-4}\). Since each \(H_2O\) molecule has \(3\) atoms, the number of atoms = \(3 \times 10^{-4} \times N_A\). For B: Molar mass of \(H_2SO_4 = 98\) g/mol. Moles of…

Apply the relevant identity from the chapter and substitute the values established in the previous step, keeping the original constraint in view.

Use the simplified expression to isolate the unknown, then plug the result back into the question setup to confirm the working is internally consistent.

Cross-check against a boundary or limiting case. Both the dimensional balance and the qualitative behaviour at the extreme should agree with the candidate answer.

Combine the steps above to identify the correct option. The remaining choices each fail at least one of the consistency, dimensional, or boundary checks.

Same subject

Explore more questions on app

From JEE Mains

Explore more questions on app