Question

After undergoing alpha decay, an atom of radium-226 becomes
a.
thorium-234
c.
uranium-238
b.
radon-222
d.
radium-224


Can someone give me an walk through

Answer 1

Alpha decay is an emission of a helium nucleus. So, that means an emission of 2 protons and 2 neutrons.

Answer 2

Mass number of radium=226
Right?

Answer 3

Anyway mass number=proton number+neutron number

Answer 4

So
226-4=?

Answer 5

U know mass of an alpha particle is = 2 proton +2 neutrons=4
Right?