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प्रश्न
What will be the molality of the solution containing 18.25 g of \[\ce{HCl}\] gas in 500 g of water?
विकल्प
0.1 m
1 M
0.5 m
1 m
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उत्तर
1 m
Explanation:
The number of moles is given by the following formula,
Moles = `"Mass"/"Molar mass"` ......(1)
The number of moles of \[\ce{HCl}\] is calculated by using equation (1) as follows,
Moles of HCl = `(18.25 g)/((36.5 g)/(mol)` = 0.5 mol
The morality (m) is given by the formula:
m = `"n"/"mass of solvent"_((kg))`
On substituting the values in the above equation:
Molality = `(0.5 mol xx 1000 kg)/500` = 1 m
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