1. UNIT 2 NUCLEAR REACTIONS 7
UNIT 2 NUCLEAR REACTIONS 7.4 What are natural and artificial transmutations?
May 19, 2010
AIM: What is the difference between artificial and natural transmutations
DO NOW:
What subatomic particle is negatively charged?
2. Write the nuclear decay equation for gold‐198.
3. If 1/8 of C‐14 is left over, how many half‐lives
did the sample undergo
Electron (e-)
79Au -1β Hg
½ x ½ x ½ = 1/8, so 3 half lives

2. REVIEW
Spontaneous Decay is when an unstable radioactive nuclei changes into a stable isotope.
Every decay reaction we looked at so far represents spontaneous decay

3. TRY
Write the spontaneous decay reaction for:
1. K‐42
2. Radon‐222

4. NATURAL AND ARTIFICIAL TRANSMUTATION
______________________ is a reaction in which we change one element to _________________element.
• There are two kinds of transmutation reactions:
1. __________________________________
2. __________________________________
different
NATURAL
ARTIFICIAL

5. For this change to happen, high‐energy particles are fired
NATURAL
ARTIFICIAL
For this change to happen,
high‐energy particles are fired
at the element.
The element undergoes
spontaneous decay because
it is unstable.
These reactions occur
“spontaneously” (on its own)
In this reaction, two things are being
combined:
(1) The nucleus being bombarded
(2) The high‐energy particle
We start with ONE element on the
RIGHT side of the arrow and end
up with TWO things on the product
side (right
side)
We start with TWO things on
the left side of the arrow and 2 or
more things on the right side of
the arrow

6. TRY THESE Natural Natural Natural Artificial Natural Artificial

7. Balancing natural and artificial transmutation reactions
Remember the law of conservation of mass! We must have a balanced equation!

8. Balance the equation 4 2 4 He 2

10. INDEPENDENT PRACTICE Complete the PRACTICE section
Please complete the classwork