# What is the net reaction for the nuclear decay chain of "U"-234?

Jul 25, 2017

$\text{_92^234"U" → ""_82^206"Pb" + 7color(white)(l)""_2^4"He" + 4color(white)(l)""_text(-1)^0"e}$

#### Explanation:

Uranium-234 decays to lead-206 in a series of 11 steps involving seven α-decays and four β-decays.

Here are the steps:

1. $\text{_92^234"U" → ""_90^230"Th" + ""_2^4"He}$
2. $\text{_90^230"Th" → ""_88^226"Ra" + ""_2^4"He}$
3. $\text{_88^226"Ra" → ""_86^222"Rn" + ""_2^4"He}$
4. $\text{_86^222"Rn" → ""_84^218"Po" + ""_2^4"He}$
5. $\text{_84^218"Po" → ""_82^214"Pb" + ""_2^4"He}$
6. $\text{_82^214"Pb" → ""_83^214"Bi" + ""_text(-1)^0"e}$
7. $\text{_83^214"Bi" → ""_84^214"Po" + ""_text(-1)^0"e}$
8. $\text{_84^214"Po" → ""_82^210"Pb" + ""_2^4"He}$
9. $\text{_82^210"Pb" → ""_83^210"Bi" + ""_text(-1)^0"e}$
10. $\text{_83^210"Bi" → ""_84^210"Po" + ""_text(-1)^0"e}$
11. $\text{_84^210"Po" → ""_82^206"Pb" + ""_2^4"He}$

Add them all up, and you get the overall equation

$\text{_92^234"U" → ""_82^206"Pb" + 7color(white)(l)""_2^4"He" + 4color(white)(l)""_text(-1)^0"e}$