14.5k views
5 votes
238,2U --> 234Th +
90

1 Answer

3 votes

Answer:


\\_(2)^(4) \alpha

Step-by-step explanation:

In this question, we wish to find the missing nuclei for the equation:


\\_(92)^(238) U\rightarrow _(90)^(234) Th + _(Z)^(A) X

In order to find the missing species, we need to use the charge and mass balance law. That is, the mass should be conserved: the total mass on the left-hand side with respect to the arrow should be equal to the total mass on the right-hand side with respect to the arrow:


238 = 234 + A

Notice from here that:


A = 238 - 234 = 4

So far we know that the mass of X is 4. Similarly, we apply the law of charge conservation. The total charge should be conserved:


92=90+Z

From here:


Z = 92-90=2

We have a particle:


\\_(2)^(4) X

Looking at the periodic table, an atom with Z = 2 corresponds to helium. This can also be written as an alpha particle:


\\_(2)^(4) \alpha

User Sngreco
by
7.1k points