Radioactive Isotopes

Radiometric dating is possible because the rates of decay of radioactive isotopes _____.

• change over time

• change from place to place

• are constant

• vary widely

Tags

NGSS.HS-PS1-8

If the half-life of a radioactive group of atoms is 100 years, then how old is the rock if there have been two half-lives?

• 25 years

• 200 years

• 400 years

• 800 years

Tags

NGSS.HS-PS1-8

How many grams of Carbon-14 will remain after 17,100 years- C-14 has a half life 5,730 so 17,100 is about 3 half lives?

• 32 g

• 16 g

• 8 g

• 4 g

What percentage of Rubidium-87 will remain after 4 half-lives?

• 25%

• 12.5%

• 6.25%

• 3.125%

Tags

NGSS.HS-PS1-8

Match the radioactive isotope to its decay product (daughter).

• Nitrogen-14

• ^Potassium-40

• Strontium-87

• ^Carbon-14

• Lead-206

• ^Uranium-238

• Calcium-40

• ^Rubidium-87

Tags

NGSS.HS-PS1-8

What is the name given to an "unstable" isotope?

• radioactive

• radioisotopes

• photon

• electron cloud

Tags

NGSS.HS-PS1-8

Which of these describes the use of the carbon-14 isotope?

• formed by radioactive decay

• cannot beused to date objects

• can be used to date objects more than 6,000 years old

• can be used to date objects less than 75,000 years old

Tags

NGSS.HS-PS1-8

Match the following

• Pb206

• U238

• Ar40

• potassium 40

• Sr87

• C14

• N14

• Rb87

Tags

NGSS.HS-PS1-8

The ​ (a)   isotope changes naturally over time as they decay.

• unstable

• stabe

• constant

• element

Tags

NGSS.HS-PS1-8

Carbon-14 decomposes into ​ (a)  

• Nitrogen-14

• Nitrogen-12

• Uranium

• Lead

• Argon

• Potassium

Tags

NGSS.HS-PS1-8