Question

study guide for nuclear chemistry

1. what determines if an atom will be radioactive or unstable?
2. the three principle types of radioactive decay are alpha beta decay

use the following answer choices for question 3 - 15
a. alpha particles
b. beta particles
c. gamma rays
d. alpha and beta particles
e. beta particles and gamma rays
f. all of the above

1. described as a fast moving electron
2. has a positive charge
3. has no mass or atomic number
4. changes both the mass number and atomic number in radioactive decay
5. a helium nucleus
6. electromagnetic radiation
7. cannot be stopped by human skin or a piece of paper
8. largest type of radioactive decay
9. transmutation reaction
10. most damaging and most penetrating
11. particle released when carbon - 14 changes to nitrogen - 14
12. emission increases the stability of the nucleus
13. not deflected by any magnetic or electrical fields
14. write the nuclear decay equation for thorium - 230 undergoing alpha decay
15. write the nuclear decay equation for $_3^6li$ emitting a beta particle.
16. thorium - 234 can undergo beta particles production. what is the other product?

Explanation:

Step1: Recall nuclear - chemistry concepts

For question 1, an atom's radioactivity depends on the neutron - to - proton ratio. For 16, thorium - 230 (atomic number 90) in alpha decay: $^{230}_{90}Th
ightarrow^{226}_{88}Ra + ^{4}_{2}He$. For 17, $^{8}_{3}Li
ightarrow^{8}_{4}Be+^{0}_{- 1}e$. For 18, thorium - 234 (atomic number 90) in beta decay gives protactinium - 234 (atomic number 91), $^{234}_{90}Th
ightarrow^{234}_{91}Pa+^{0}_{-1}e$.

Answer:

1. Neutron - to - proton ratio
2. $^{230}_{90}Th

ightarrow^{226}_{88}Ra + ^{4}_{2}He$

1. $^{8}_{3}Li

ightarrow^{8}_{4}Be+^{0}_{- 1}e$

1. Protactinium - 234 ($^{234}_{91}Pa$)