Question

calculate molarity of 2.5 g of ethanoic acid in 75 grams of benzene
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Answer 1

Answer:

The molar mass of ethanoic acid is 2(12)+2(16)+4(1)=60 g/mol. The mass of ethanoic acid is divided with molar mass of ethanoic acid to obtain number of moles of ethanoic acid.

Number of moles of ethanoic acid =  

60g/mol  

2.5g

​  

=0.04167mol

The mass of benzene is 75 grams or  

1000  divided by75 =0.075 kg.

The molality of ethanoic acid in benzene is the ratio of the number of moles of ethanoic acid to the mass of benzene (in kg).  

It is  

0.075kg

0.04167mol

​=0.556m

Explanation: