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
Text Solution
Verified by Experts
The correct Answer is:
A
1 watt = 1 J/sec Total heat supplied for 36 mL `H_(2)O` `" "=806 xx 100` `" "=80600 J` `" "DeltaH_("vap")=(80600)/(36)xx18` `" "=40300" J or 40.3 kJ"//"mol"`
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