3D Half Life

Multiple Choice

When an isotope goes through 3 half-lives __________ remains.

• 1/32 or 3.125%

• 1/8 or 12.5%

• 1/16 or 6.25%

Multiple Choice

When an isotope goes through 4 half-lives ________ remains.

• 1/4 or 25%

• 1/8 or 12.5%

• 1/16 or 6.25%

Multiple Choice

When an isotope goes through 2 half-lives _____________ remains.

• 1/4 or 25%

• 1/2 or 50%

• 1/8 or 12.5%

Multiple Choice

How much of an 80 g sample will remain after 21.2 years?

• 40 g

• 20 g

• 10 g

• 5 g

Multiple Choice

How many years will it take for an 80 g sample to decay to 10 g? (Remember: you must add 5.3 years for each half-life)

• 10.6 years

• 15.9 years

• 21.2 years

• 26.5 years

Multiple Choice

If 20 g of copper-64 has a half-life of 13 hours, what mass will remain after 39 hours?

• 10 g

• 5 g

• 2.5 g

• 1.25 g

Multiple Choice

If 20 g of copper-64 has a half-life of 13 hours, what mass of copper-64 will remain after 26 hours?

• 10 g

• 5 g

• 2.5 g

• 1.25 g

Determining Half Life from a Graph

https://youtu.be/qqzFCO_n5Vg

Multiple Choice

What is the half-life of radium-226 in the graph?

• 1600 years

• 3200 years

• 4800 years

• 6400 years

Multiple Choice

What is the half-life of strontium-90?

• 25 years

• 50 years

• 100 years

• 150 years

Multiple Choice

How many grams will remain after 100 g of cobalt-60 has gone through 3 half-lives?

• 50 g

• 25 g

• 12.5 g

• 6.25 g

Multiple Choice

How many years will it take for 75% of 100 g of cobalt-60 to decay?

• 5 years

• 10 years

• 15 years

• 30 years

The End