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In order to decompose 9 grams of water 1...

In order to decompose 9 grams of water 142.5 KJ heat is required. Hence the enthalpy of formation of water is

A

`-142.5 kJ`

B

`+142.5 kJ`

C

`-285 kJ`

D

`+285 kJ`

Text Solution

Verified by Experts

The correct Answer is:
C
Heat required to decompose `1` mol `(18)g` of `H_(2)O=2xx142.5=285kJ`
`DeltaH_(f)` is the reverse of heat required `=285 kJ mol^(-1)`
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