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# Calculating Enthalpy Change Tweet

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1. Calculating Enthalpy Change
6) Use your answer from question 5 (6.8) to calculate the heat given out during this experiment. Assume a density of 1.00gcm-³ and a specific heat capacity of 4.18.

q=mc(Delta)T
q= 1x4.18x6.8
q=28.4/1000
q=0.0284kjmol-1
7) The HCl used in Task 1 had a concentration of 1.00moldm-³. Calculate the amount, in moles, of HCl present in the 25.0cm³ (0.025dm³) of this acid.

1.00x0.025 = 0.025mol
How would I do this question?

8) Use your answers from questions 6 and 7 to calculate the enthalpy change, in kJmol-1, for the reaction between one mole of HCl and the glass cleaner.
2. Re: Calculating Enthalpy Change
(Original post by LukeyJB)
How would I do this question?

8) Use your answers from questions 6 and 7 to calculate the enthalpy change, in kJmol-1, for the reaction between one mole of HCl and the glass cleaner.
Use the formula:

Since heat is given out, the reaction is exothermic, and thus delta H is negative. Therefore,