Why are reaction orders not always equal to the coefficients in a balanced chemical equation?

Also, the reaction order does not correspond to the stoichiometric coefficients; it's only a coincidence here. The reaction order only says how many molecules per mole participate in the reaction (molecularity is usually a good indication), not how many moles of each molecule there are (stoichiometric coefficients).

Explanation:

it is to be noted that an alpha particle is an helium nucleus. so it contains 2 protons 2 neutrons and has a mass number of 4. when alpha decay particles are ejected from the nucleus it gets transformed into an atom which has atomic number less than 2 and a mass number less than 4.

an equation that could represent alpha decay is radium 226 decay of alpha particle forms radon 222.

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