NUCLEUS EMITS RADIOACTIVITY

SUMMARY OF KEY REACTIONS

1.Beta [β] emission . When a nucleus decays by beta emission , the new element has the same mass number but an atomic number one unit greater.

³²P₁₅→ ³²S₁₆ + ⁰e_-1

2.Alpha [α] . When a nucleus decays by alpha emission , the new nucleus has a new mass number four units smaller and an atomic number two units smaller.

²³⁸P₉₂ → ²³⁴Th₉₀ + ⁴He₂

3.Positron [β⁺] emission . When a nucleus decays by positron emission , the new element has the same mass but an atomic number one unit smaller.

¹¹C₆ → ¹¹B₅ + ⁰e₊₁

4. Gamma [γ] emission . When a nucleus emits gamma radiation , there is no change an either mass number or atimic number of the nucleus.

¹¹B₅ → ¹¹B₅ + γ

5.Electron capture . When a nucleus decays by electron capture , the product nucleus has the same mass number but an atomic number one unit smaller.

⁷Be₄ + ⁰e₁ → ⁷Li₃

_{Exercise 1}

b. a. ¹³C₆ + ⁴He₂ → ¹⁶O₈ + ?

d. b.¹²C₆ + ¹H₁ → ? + γ

a. C. ¹³C₆ + ⁴He₂ → ¹⁶O₈ + ?

a. d. ²¹⁰Bi₈₃ → ? + ⁰e_-1

a. e. ¹²C₆ + ¹H₁ → ? + γ

s f. Americium- 240 is made by bombarding plutonium- with α particles. In addition to americium- 240, a proton and two neutrons are formed. Write a balanced equation for this nuclear reaction.

g. For each of the following, write a balanced nuclear equation and identify the radiation emitted.

1. Beryllium-10 changes to Boron-10

2. Thallium – 195 changes to Mercury- 195

3. Plutonium – 239 changes to Uranium -235