# chem-help pls!

When 0.975 g of CaO is added to 200.0 mL of 0.500 M HCl(aq), a temperature increase of 400C is observed.
Assume the solution's final volume is 200.0 mL, the density is 1.00 g/mL, and the heat capacity is 4.184 J/gC.

Hrxn, for the reaction of

CaO(s) + 2H+(aq) Ca2+(aq) + H2O(l)

is______ kJ/mol.

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1. The 400 C still bothers me. Could that be 40.0 C? Also, you need to learn (and quickly) to put arrows in the equation. Without arrows how are we to know which are reactants and which are products?

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2. CaO (s) + 2H(aq) --->Ca2 (aq)+H20 (l)

it's 4.00 C. sorry about the earlier format

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3. How much heat is transferred to the water?
q = massH2O x specific heatH2O x delta Tof H2O = ?? J
Then convert 0.975 g CaO to mols and divide to obtain J/mol. Convert that to kJ/mol.

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