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In order to decompose 9g water 142.5 kJ ...

In order to decompose 9g water 142.5 kJ heat is required. Hence, the enthalpy of formation of water is

A

-142.5 kJ/mole

B

+142.5 kJ/mole

C

-285 kJ/mole

D

+285 kJ/mole

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The correct Answer is:
C
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