10.2 Radioactive Decay and Disintegration Rate

What is the original size of the sample in the first graph?

• 100 grams

• 75 grams

• 50 grams

• 25 grams

What is HALF the original amount in the first graph?

• 50 grams

• 25 grams

• 75 grams

• 10 grams

How long did it take to reach ½ the original amount in the first graph?

• 25 years

• 50 years

• 75 years

• 100 years

What is the original size of the sample in the second graph?

• 16,000 decays per minute

• 12,000 decays per minute

• 8,000 decays per minute

• 4,000 decays per minute

Tags

NGSS.HS-PS1-8

What is HALF the original amount in the second graph?

• 8,000 decays per minute

• 4,000 decays per minute

• 12,000 decays per minute

• 2,000 decays per minute

Tags

NGSS.HS-PS1-8

How long did it take to reach ½ the original amount in the second graph?

• 4 days

• 8 days

• 12 days

• 16 days

Tags

NGSS.HS-PS1-8

The half-life of radon-222 is 3.8 days. How much of a 100g sample is left after 15.2 days?

• 6.25 grams

• 12.5 grams

• 25 grams

• 50 grams

Carbon-14 has a half-life of 5730 years. If a sample starts with 70 mg of Carbon-14, how much is left after 17190 years?

• 8.75 mg

• 17.5 mg

• 35 mg

• 70 mg

How much of a 500-g sample of potassium-42 is left after 62 hours if the half-life of K-42 is 12.4 hours?

• 15.625 g

• 31.25 g

• 62.5 g

• 125 g

Tags

NGSS.HS-PS1-8

The half-life of cobalt-60 is 5.26 years. How much Co-60 is left from a 401g sample after 15.8 years?

• 50.125 g

• 100.25 g

• 200.5 g

• 25.0625 g

Tags

NGSS.HS-PS1-8