JEE Mains · Chemistry · STD 11 - 1. Some basic concept of chemistry
\(6.023 \times 10^{22}\) molecules are present in \(10 \,g\) of a substance \('x'.\) The molarity of a solution containing \(5\, g\) of substance \({ }^{\prime} x ^{\prime}\) in \(2\, L\) solution is.......... \(\times 10^{-3}\)
- A \(20\)
- B \(25\)
- C \(22\)
- D \(18\)
Answer & Solution
Correct Answer
(B) \(25\)
Step-by-step Solution
Detailed explanation
moles \(=\frac{\text { number of molecules }}{6 \times 10^{23}}=\frac{\text { given mass }}{\text { molar mass }}\) \(\Rightarrow\) molar mas \(=\frac{10 \times 6.023 \times 10^{23}}{6.023 \times 10^{22}}=100 g / mol\) \(\Rightarrow\) molarity…
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