Among the following choose the ones with equal number of atoms. A. 212 g of Na 2 CO 3 ( s ) [molar mass =106 g ] B. 248 g of Na 2 O ( s ) [molar mass =62 g ] C. 240 g of NaOH ( s ) [molar mass =40 g ] D. 12 g of H 2 ( g ) [molar mass =2 g ] E. 220 g of CO 2 ( g ) [molar mass =44 g ] Choose the correct answer from the options given below:

Chemistry · Some Basic Concepts of Chemistry (Mole Concept) + Stoichiometry

NEET (UG) 2025 — Question 63

Among the following choose the ones with equal number of atoms.

A. 212 g of $\mathrm{Na}_{2} \mathrm{CO}_{3}(\mathrm{~s})$ [molar mass $=106 \mathrm{~g}$ ]

B. 248 g of $\mathrm{Na}_{2} \mathrm{O}(\mathrm{s})$ [molar mass $=62 \mathrm{~g}$ ]

C. 240 g of $\mathrm{NaOH}(\mathrm{s})$ [molar mass $=40 \mathrm{~g}$ ]

D. 12 g of $\mathrm{H}_{2}(\mathrm{~g})$ [molar mass $=2 \mathrm{~g}$ ]

E. 220 g of $\mathrm{CO}_{2}(\mathrm{~g})$ [molar mass $=44 \mathrm{~g}$ ]

Choose the correct answer from the options given below:

No. of atoms $=$ Atomicity $\times$ mole $\times \mathrm{N}_{\mathrm{A}}$

(A) No. of atoms $=6 \times \frac{212}{106} \times \mathrm{N}_{\mathrm{A}}=12 \mathrm{~N}_{\mathrm{A}}$

(B) No. of atoms $=3 \times \frac{248}{62} \times \mathrm{N}_{\mathrm{A}}=12 \mathrm{~N}_{\mathrm{A}}$

(D) No. of atoms $=2 \times \frac{12}{2} \times \mathrm{N}_{\mathrm{A}}=12 \mathrm{~N}_{\mathrm{A}}$

(E) No. of atoms $=3 \times \frac{220}{44} \times \mathrm{N}_{\mathrm{A}}=15 \mathrm{~N}_{\mathrm{A}}$

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Exam: NEET (UG) 2025
Paper: 2025 paper
Subject: Chemistry
Chapter: Some Basic Concepts of Chemistry (Mole Concept) + Stoichiometry
Topic: Composition of Matter, Atoms, Molecules and Laws of Chemical Combination