Half Life

The diagram shows 32 atoms

32 of the Red are the parent isotope

0 of the atoms are daughter isotopes

How many half-lives have occurred?

• 0

• 1

• 2

• 3

Tags

NGSS.HS-PS1-8

The diagram shows 32 atoms.

16 of the Red are parent isotopes

16 of the Green are daughter isotopes

How many half-lives have occurred?

• 0

• 1

• 2

• 3

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 technetium-99 isotope has a half-life of 6.0 hours. If 100.0 mg were injected into a patient how much remains after 18 hours?

• 33.0 mg

• 12.5 mg

• .33 mg

• 15.8 mg

What is the half-life of an isotope if after 20.0 days you have 4.0 grams remaining of a 64.0 grams sample?

• 25 days

• 5.0 days

• 80 days

• 4.25 days

If the half-life of uranium-232 is 70 years, how many half-lives will it take for 10 g of it to be reduced to 1.25 g?

• half-life

• half-lives

• half-lives

• half-lives

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

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

When nuclei decay, massive amounts of __________ is released.

• energy

• jello

• protons

• neutrons

Tags

NGSS.HS-PS1-8

The % of the parent isotope remaining after 1 Half Life.

• 50%

• 25%

• 12.5%

• 6.25%

Tags

NGSS.HS-PS1-8