Half-Life Quiz 1.0

A 200 g sample of carbon-14 decays to 25 g in 17,190 years. What is the half-life of carbon-14?

• 5,730 years

• 11,460 years

• 22,920 years

• 34,380 years

Thorium-234 has a half-life of 24.1 days. How long will it take for a 160 g sample to decay to 10 g?

• 96.4 days

• 120.5 days

• 72.3 days

• 144.6 days

Tags

NGSS.HS-PS1-8

Polonium-214 has a half-life of 0.00016 seconds. How long will it take for a 500 g sample to decay to 62.5 g?

• 0.00032 seconds

• 0.00048 seconds

• 0.00064 seconds

• 0.00096 seconds

Tags

NGSS.HS-PS1-8

A 300 g sample of iodine-131 decays to 37.5 g in 24.0 days. What is the half-life of this isotope?

• 6.0 days

• 8.0 days

• 12.0 days

• 4.0 days

Tags

NGSS.HS-PS1-8

A 50 g sample of thorium-230 decays to 3.125 g in 3.2 million years. What is the half-life of thorium-230?

• 1.6 million years

• 0.8 million years

• 2.4 million years

• 3.2 million years

Tags

NGSS.HS-PS1-8

A 480 g sample of uranium-234 decays to 15 g in 95 days. What is the half-life of uranium-234?

• 15 days

• 19 days

Tags

NGSS.HS-PS1-8

Strontium-90 has a half-life of 28.8 years. How much of a 40 g sample will remain after 115.2 years?

• 2.5 g

• 5.0 g

• 10.0 g

• 1.25 g

Tags

NGSS.HS-PS1-8

The half-life of tritium is 12.3 years. How much of a 10 g sample will remain after 49.2 years?

• 2.5 g

• 1.25 g

• 5.0 g

• 0.625 g

Tags

NGSS.HS-PS1-8

Plutonium-239 has a half-life of 24,100 years. How much of a 200 g sample will remain after 48,200 years?

• 100.0 g

• 25.0 g

• 50.0 g

• 12.5 g

Tags

NGSS.HS-PS1-8

How many half-lives are required for a sample to decay to 1/32 of its original mass?

• 3 half-lives

• 4 half-lives

• 5 half-lives

• 6 half-lives