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Calculate molality of 2.5g of ethanoic a...

Calculate molality of `2.5g` of ethanoic acid `(CH_(3)COOH)` in `75 g` of benzene.

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Molar mass of `C_(2)H_(4)O_(2):12xx2+1xx4+16xx2=60" g "mol^(-1)`
moles of `C_(2)H_(4)O_(2)=(2.5g)/(60" g "mol^(-1))=0.0417mol`
Mass of benzene in kg `=75g//1000g" "kg^(-1)=75xx10^(-3)kg`
Molality of `C_(2)H_(4)O_(2)=("Moles of "C_(2)H_(4)O_(2))/("kg of benzene")=(0.0417" mol "xx1000" g "kg^(-1))/(75g)`
`=0.556" mol "kg^(-1)`.
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NCERT-SOLUTION-EXERCISE
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