Dating Rocks (Relative Dating, Radioactivity, Radiometric Dating)

Scientists use radioactive decay to measure...

• relative time
• absolute time
• half-lives
• time of day

Tags

NGSS.HS-PS1-8

The length of time required for half of the radioactive atoms in a sample to decay is its...

• era
• age
• half-life
• eon

Tags

NGSS.HS-PS1-8

How does absolute age differ from relative age?

• only absolute dating indicates which rock is older than another
• only absolute dating finds the age in years
• only relative dating finds the age in years

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

The original element that undergoes radioactive decay is known as the...

• daughter element
• half-life
• parent element
• carbon-14

Tags

NGSS.HS-PS1-8

The element that is the product of radioactive decay is known as the...

• daughter element

• half-life

• parent element

• carbon-14

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

Tags

NGSS.HS-PS1-8

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

• 25%

• 12.5%

• 6.25%

• 3.125%

You find a rock sample with radioactive atoms present.  If 25% of the original radioactive atoms were present, how many half-lives has the rock been around for? (Hint, at Half-Life = 0, you start with 100%)

• zero
• 1
• 2
• 3

Tags

NGSS.HS-PS1-8