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प्रश्न
What will be the molarity of a solution, which contains 5.85 g of NaCl(s) per 500 mL?
विकल्प
4 mol L–1
20 mol L–1
0.2 mol L–1
2 mol L–1
उत्तर
0.2 mol L–1
Explanation:
No. of mole = `"Given mass"/"Molar mass"`
On substituting the value in the above equation, the cal, can be calculated as no, of mole = `(5.85 "g")/(58.5 "g mol"^-1)` = 0.1 g
The molarity (M) is given by the formula:
M = `n/V_((L))`
On substituting the values in the above equation:
Molarity = `(0.1 "mol" xx 1000 L)/500` = 0.2 mol L–1
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