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36 mL of pure water takes 100 sec to eva...

36 mL of pure water takes 100 sec to evaporate from a vessel when a heater of 806 watt is used. The `DeltaH_("vaporisation")` of `H_(2)O` is (density of water `=1g//c c)`
(a)`40.3 kJ//mol`
(b)`43.2 kJ//mol`
(c)`4.03 kJ//mol`
(d)None of these

A

`40.3kJ//mol e`

B

43.2 kJ/mole

C

4.03 kJ/mole

D

none

Text Solution

Verified by Experts

The correct Answer is:
A
1 watt=1J/sec
Total heat for 36 mL `H_(2)O`
`=806xx100` ltbr. `=80600J`
`DeltaH_("vaporisation")=(80600)/(36)xx18`
`=40300J` or `40.3kJ//mol e`
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