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Question
A 2.19-g sample of solid calcium reacted in excess fluorine gas to give a 4.27-g sample of pure solid CaF2. The heat given off in this reaction was 67.0kJ at constant pressure. Given this information, what is the enthalpy of formation of CaF2(s)?
A) 67.0 kJ/mol
B) -67.0 kJ/mol
C) -1.23 x103kJ/mol
D) -613 kJ/mol
E) 1.23 x103kJ/mol
Answer
This answer is hidden. It contains 1 characters.
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