HELP!!!!!!!!!!!! ASAP!!!!!!!!!!!!!!!!!!! CHEMISTRY TEST!!!!!!!!!!!!!! 53 POINTS

Chemistry

1 answer:

lbvjy [14]3 years ago

3 0

Answer:

9.1 KJ

Explanation:

First we must find the number of moles of HBr involved;

number of moles of HBr= mass of HBr/ molar mass of HBr

But molar mass of HBr= 80.91 g/mol

Given mass of HBr from the question= 20.1g

Hence;

Number of moles of HBr= 20.1 g/80.91g

Number of moles of HBr= 0.25 moles of HBr

If 2 moles of HBr has a heat of formation of 72.80KJ

Then 0.25 moles of HBr will have a heat of formation of 0.25× 72.80/2= 9.1 KJ

Therefore; 20.1 g of HBr will have a heat of formation of 9.1 KJ

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Oksanka [162]

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