Question

but combination reaction is opposite of decomposition reaction so, therefore we can say that decomposition reaction and dissociation reaction is same???

Answer 1

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decomposition reaction takes place between elements and compounds, but the dissociation takes place between the ions in the solution or compounds.

Answer 2

as we know that combination reaction is opposite of decomposition reaction because in combination reaction two compounds or element join together to form compound whereas in decomposition reaction a compound breaks into two or more compounds or elements.

dissociation reaction and decomposition reaction at same because in both the reaction one compound breaks to form two or more compounds of elements.

I hope my answer will help you.