The rate constants for decomposition of acetaldehyde have been measured over the temperature range $$700 - 1000$$ K. The data has been analysed by plotting $$\ln k$$ vs $$\frac{10^3}{T}$$ graph. The value of activation energy for the reaction is ______ kJ mol$$^{-1}$$. (Nearest integer) (Given : $$R = 8.31$$ J K$$^{-1}$$ mol$$^{-1}$$)