Rmeation (molecular sieve ) Chlorlaluysupny Explain the difference between the internal standard and external standard validation methods.

The activation energy for the reaction no2(g)+co2(g)⟶no(g)+co(g) is ea = 300 kj/mol and the change in enthalpy for the reaction is δh = -100 kj/mol . what is the activation energy for the reverse reaction?