Radium-226 decays by alpha emission. What is its decay product?

The decay of Radium-226  will result in the products which is referred to as

Radon and Helium

It is represented by Rn and has a mass number of 222 and an atomic number

of 86. Alpha emission involves the creation of a new product and Helium

atom.

This simply means that the mass number of the  parent element will be

reduced by 4 and the atomic number will be reduced by 2. This thereby

gives rise to  ²²²₈₆Rn.

The explanation is shown in the attachment below.

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Radon-222 (i.e 222 86 Rn)

Explanation:

When an element undergoes alpha decay, the resulting daughter nuclei will have a decrease of 4 in the mass number and a decrease of 2 in the atomic number when compared to the parent nucleus.

When Radium-226 decays by alpha emission it will produce Radon-222.

Please see attached photo for explanation.

i think it is d. e because the next one is igneous.

if you mean hydrogen and oxygen then water is the product