# Worksheet: Radioactive Decay Chains

In this worksheet, we will practice determining the products of radioactive decay chains and identifying the type of radioactive decay from the decay products.

**Q1: **

Astatine-218 undergoes beta decay to radon-218. Radon-218 undergoes alpha decay to polonium-214. This is shown in the following nuclear equation:

What is the value of in the equation?

What is the value of in the equation?

**Q2: **

Which type of nuclear radiation has no mass?

- ABeta particles
- BGamma rays
- CNeutrons
- DAlpha particles

**Q3: **

The diagram shows a beryllium-11 nucleus undergoing two-step radioactive decay. Red circles represent protons, gray circles represent neutrons, and blue circles represent electrons. What isotope is produced through this reaction?

- ABeryllium-11
- BLithium-7
- CBoron-11
- DCarbon-12
- EBeryllium-9

**Q5: **

Uranium-234 decays via alpha decay to thorium-230. Thorium-230 then decays via alpha decay to radium-226. This is shown in the following nuclear equation:

How many protons in total are ejected from a uranium nucleus that undergoes this process?

How many nucleons in total are ejected from a uranium nucleus that undergoes this process?

**Q6: **

Which type of nuclear radiation has the greatest mass?

- ANeutrons
- BBeta particles
- CAlpha particles
- DGamma rays

**Q7: **

Which type of nuclear radiation has the smallest nonzero mass?

- ANeutrons
- BAlpha particles
- CGamma rays
- DBeta particles

**Q8: **

Beryllium-11 is an isotope of beryllium with a half-life of just 13.8 seconds. It can undergo a two-step decay to an isotope of lithium, as shown in the diagram. Red circles represent protons, grey circles represent neutrons, and blue circles represent electrons. What two types of decay does the beryllium nucleus undergo in order to become lithium?

- AAlpha decay then beta decay
- BBeta decay then alpha decay
- CGamma decay then beta decay
- DBeta decay then gamma decay
- EAlpha decay then gamma decay

**Q9: **

Thorium-232 undergoes alpha decay to radium-228. Radium-228 then undergoes beta decay to actinium-228. This is shown in the following nuclear equation.

What is the change in the the atomic number of the nucleus in its decay from a thorium nucleus to an actinium nucleus?

What is the change in the the mass number of the nucleus in its decay from a thorium nucleus to an actinium nucleus?

**Q10: **

Polonium-218 has a small probability of decaying via beta decay to astatine-218. Astatine-218 has a small probability of decaying via beta decay to radon-218. This is shown in the following nuclear equation:

What is the value of in this nuclear equation?

What is the value of in this nuclear equation?