Radioactive Decay and Half-Life

Which type of nuclear radiation is being emitted here?

• Alpha

• beta

• gamma

• none

Tags

NGSS.HS-PS1-8

After the third half-life, how much of the sample is left?

• 1/2

• 1/3

• 1/16

• 1/8

Tags

NGSS.HS-PS1-8

The half-life of strontium-90 is 25 years. How much strontium-90 will remain after 100 years if the initial amount is 4.0 g?

• 3.0g

• 0.25mg

• 0.3g

• 0.25g

Tags

NGSS.HS-PS1-8

You have 100 grams of radioactive C-14. The half life of C-14 is 5730 years. 
How many grams are left after 1 half life? 

• 100 grams

• 25 grams

• 2 grams

• 50 grams

Tags

NGSS.HS-PS1-8

The time it takes for 50% of the nuclei in a radioactive sample to decay to its stable isotope is called _____.

• the daughter product

• geologic time

• the half-life

• the half-time

Tags

NGSS.HS-PS1-8

After 2 half lives, what percent is the parent isotope?

• 100%

• 50%

• 75%

• 25%

Tags

NGSS.HS-PS1-8

After 4 half-lives, 1g of a sample of Krypton-85 remains unchanged.  What was the original mass of the sample?

• 16g

• 32g

• 0.0625g

• 4g

Tags

NGSS.HS-PS1-8

How long is one half life of C-14

• 5730

• 11460

• 17190

• 28650

Half-life

• A measurement of the total number of protons and neutrons in an element

• atoms of the same element with different numbers of neutrons

• The spontaneous release of material from the nucleus of radioactive isotopes

• The time it takes for 1/2 of an original radioactive atom to decay

Tags

NGSS.HS-PS1-8

Radioactive materials have unstable...

• electrons

• protons

• nuclei

• neutrons

Tags

NGSS.HS-PS1-8