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Alevel energetics help

So the question is:

Student added 0.0210 mol CuSO4 to 25.0cm3 of deionised water. Exothermic reaction occurred and temp of water increased 14C

Use this data to calculate the Enthalpy change for this reaction of copper (II) sulfate. This is the student value for delta H 1

In this experiment you should assume that all the heat releases is used to raise temp of 25g of water. The specific heat capacity is 4.18Jk-1g-1

My Answer:

So I did Q=mc delta T

And got the correct answer of 1463J

But now I’m confused of how to work out the enthalpy enthalpy change for 0.0210 mol. The correct answer is -69.67 but I don’t know how they got that value.

Any help would be much appreciated. Thanks
Original post by chloe0804
So the question is:

Student added 0.0210 mol CuSO4 to 25.0cm3 of deionised water. Exothermic reaction occurred and temp of water increased 14C

Use this data to calculate the Enthalpy change for this reaction of copper (II) sulfate. This is the student value for delta H 1

In this experiment you should assume that all the heat releases is used to raise temp of 25g of water. The specific heat capacity is 4.18Jk-1g-1

My Answer:

So I did Q=mc delta T

And got the correct answer of 1463J

But now I’m confused of how to work out the enthalpy enthalpy change for 0.0210 mol. The correct answer is -69.67 but I don’t know how they got that value.

Any help would be much appreciated. Thanks

0.021 mol of CuSO4 gives 1463 J of energy
so 1 mol gives ... ?
convert in kJ then you have the enthalpy change in kJ/mol
make sure to put an appropriate sign

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