Name: __________________________________________ Period: ___ Date: _________

 

Dekalb Reads Assignment 7.1 B

Nuclear Decay

Read pages 222-227 and answer the following questions

 

1.      What happens when an unstable nucleus emits alpha or beta particle?

2.      What change takes place when Radiuin-226 emits an alpha particle?

3.      What does a nucleus give up in an alpha decay?

4.      Write an equation that represents alpha decay.

5.      Study the above equation (# 4)  and answer the questions a-d:

1. How many protons are there on product side? _______
2. Is this equal to the # of protons in Ra? __________
3. What is the sum of the mass # of products? _________
4. Is it equal to the mass # of Ra? __________________

6.      What happens during beta decay?

7.      Give an example of beta decay.

8.      What remains unchanged during beta decay?

9.      What happens when a nucleus undergoes decay b gamma rays?

10.  Define half-life.

11.  Half life is a measure of _____________________________________________ .

12.  Name the isotope used to calculate the age of rock.

13.  Potassium-40 decays to __________________.

14.  How can you find out which rock is older?

15.  Name the isotope that the archeologists use.

16.  What happens to carbon-14 [C-14] when an animal or plant die?

17.  What happens to the ratio of C-14 to C-12 with time?