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When 1.20g of sulphur is melted with 15....

When `1.20g` of sulphur is melted with `15.00g` of naphthalene, the solution freezes at `77.2^(@)C`. What is the moalr mass of this from of sulphur. Data for Napthalene
Melting point, m.p `80^(@)C`
Freezing point depression constant, `k_(f) = 6.80^(@)Cm^(-1)`

A

`180 g mol^(-1)`

B

`194 g mol^(-1)`

C

`260 g mol^(-1)`

D

`450 g mol^(-1)`

Text Solution

Verified by Experts

The correct Answer is:
B
`2.8 = (1.2)/(15 xx x) xx 10^(3) xx 6.8`
`x = 194`
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