k=AeRT−Ea
lnk=lnA−RTEa
lnk=lnA+[1000R−Ea]T1000
Slope =1000R−Ea=−18.5
Ea=18.5×1000×8.31
=153.735×103J
=154KJ
The rate constants for decomposition of acetaldehyde have been measured over the temperature range 700−1000K. The data has been analysed by plotting lnk vs T103 graph. The value of activation energy for the reaction is kJmol−1. (Nearest integer) (Given : R=8.31JK−1mol−1)

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