Half Lives

What is the Half life of this isotope?

• 5 seconds

• 10 seconds

• 15 seconds

• 20 seconds

Tags

NGSS.HS-PS1-8

What is the Half Life of this isotope?

• 3 days

• 5 days

• 8 days

• 10 days

Tags

NGSS.HS-PS1-8

The % of the parent isotope remaining after 2 Half Lives.

• 50%

• 25%

• 12.5%

• 6.25%

Tags

NGSS.HS-PS1-8

After one half life, a sample will begin to have more of the parent isotope than the daughter isotope.

• TRUE

• FALSE

Tags

NGSS.HS-PS1-8

A sample will lose half of the parent isotope after 1 half life.

• TRUE

• FALSE

Tags

NGSS.HS-PS1-8

Which is used in radioactive dating?

• Carbon-14

• Index fossils

• Hydrochloric acid

• Law of superposition

Tags

NGSS.HS-PS1-8

What is the half-life of iodine-131?

• 32 days

• 8 days

• 16 days

• 24 days

Tags

NGSS.HS-PS1-8

An isotope has a half life of 20 years. If it starts with a sample of 100g, how much of it will be left after 80 years?

• 25 grams

• 50 grams

• 6.25 grams

• 12 grams

After 2 half lives have passed, what percent of the parent isotope is left?

• 25%

• 50%

• 75%

• 100%

Tags

NGSS.HS-PS1-8

Barium-122 has a half-life of 2 minutes. A fresh sample weighing 80 g was obtained. If it takes 10 minutes to set up an experiment using barium-122, how much barium-122 will be left when the experiment begins?

• 0.25g

• 2.5g

• 25g

• 80g

Tags

NGSS.HS-PS1-7