# Chemistry

When 0.689 g of Ca metal is added to 200.0 mL of 0.500 M HCl(aq), a temperature increase of 11.2C 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.
(Note: Pay attention to significant figures. Do not round until the final answer.)
The molar heat of reaction, H rxn, for the reaction of

Ca(s) + 2H+(aq) Ca2+(aq) + H2(g)

....i got 545.19 kJ/mol but that's not rightt.....

i did 200 g x 4.184 j/gc x 11.2C = 9372.16j

9372.16j / 0.689 g = 13602 j/g

13602 j/g x 40.08 g/mol = 545 kj/mol....but for some reason its not right..whyy??

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1. I get 545 kJ/mol to three s.f.
If you typed in 545.19 or .2, that's the problem. If you typed in 545 kJ/mol, I don't know.

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