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When W(B) gm solute ( molecular mass M(B...

When `W_(B)` gm solute ( molecular mass `M_(B)`) dissolves in `W_(A)` gm solvent. The molality m of the solution is

A

`(W_(B)xxM_(B))/(W_(A)xx1000)`

B

`(W_(B)xx1000)/(M_(B)xxW_(A))`

C

`(W_(A)xx1000)/(M_(B)xxW_(B))`

D

`(W_(A)xxM_(B))/(W_(B)xx1000)`

Text Solution

Verified by Experts

The correct Answer is:
B
Number of moles of B `=(W_(B))/(M_(B)) = n_(B)`
Mass of solvent A in kg `= ( W_(A))/(1000)`
Molality of B `= ( n_(B))/(W_(A)//1000) = ( W_(B)xx1000)/(M_(B)xxW_(A))`
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