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Physics · Electric Charges and Fields
हिन्दीA sample contains \( 34\text{ g} \) of pure ammonia (\( \text{NH}_3 \)) gas. Taking Avogadro's number \( N_A = 6.02 \times 10^{23}\text{ mol}^{-1} \) and elementary charge \( e = 1.60 \times 10^{-19}\text{ C} \), the magnitude of the total positive charge contained in all the atomic nuclei of this sample is approximately:
Correct answer · Option 1
\( 1.93 \times 10^6\text{ C} \)
Explanation
Molar mass of \( \text{NH}_3 = 17\text{ g/mol} \). Moles \( = \frac{34}{17} = 2 \). Molecules \( = 2 \times 6.02 \times 10^{23} = 1.204 \times 10^{24} \). Each \( \text{NH}_3 \) molecule contains \( 7 + 3(1) = 10 \) protons. Total positive charge \( q = 1.204 \times 10^{24} \times 10 \times 1.60 \times 10^{-19}\text{ C} \approx 1.93 \times 10^6\text{ C} \).
