Q1:

A radioactive sample initially contains mol of a radioactive material which has a half-life of 6.00 hours.

Approximately how many moles of the radioactive material remain after 6.00 h?

• A mol
• B mol
• C mol
• D mol
• E mol

Approximately how many moles of the radioactive material remain after 12.00 h?

• A mol
• B mol
• C mol
• D mol
• E mol

Approximately how many moles of the radioactive material remain after 36.00 h?

• A mol
• B mol
• C mol
• D mol
• E mol

Q2:

A sample of radioactive material is obtained from a very old rock. A plot of the natural logarithm of the sample's activity versus time yields a slope value of s−1. What is the half-life of this material?

• A years
• B years
• C years
• D years
• E years

Q3:

A piece of wood from an ancient Egyptian tomb is tested for its carbon-14 activity. It is found to have an activity per gram decay/ming. What is the age of the wood? Use a value of s−1 for the decay constant of carbon-14 and a value of for the relative abundance of carbon-14.