Which of the following suggests a chemical change took place? * A. The substance is smaller than it was before the change took place.
B. A new substance has formed.
C. The substance looks the same as it did before the change took place.
D. The substance has been shaken up.

A

Explanation:

Because it got smaller so that mean it had a chemical reaction

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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