Front

What is half-life in radioactivity?

Back

The amount of time it takes for half of a radioactive sample to decay.

Front

What do isotopes have different numbers of?

Back

Neutrons.

Front

If a radioactive sample has a half-life of 8.10 days, how long will it take for a 50g sample to decay to 6.25g?

Back

24.3 days.

Front

How much of a 144 g sample of Carbon-14 will remain after 17,190 years?

Back

18 g.

Front

What is the half-life of Sodium-24 if a 208 g sample decays to 13 g in 60 hours?

Back

15 hours.

Front

Define radioactive decay.

Back

The process by which an unstable atomic nucleus loses energy by radiation.

Front

What is the formula to calculate the remaining amount of a substance after a certain number of half-lives?

Back

Remaining amount = Initial amount × (1/2)^(number of half-lives).

Front

What is an isotope?

Back

Atoms of the same element that have different numbers of neutrons.

Front

How does the half-life of a substance affect its stability?

Back

A shorter half-life indicates a less stable substance that decays quickly.

Front

What is the significance of half-life in carbon dating?

Back

It helps determine the age of ancient organic materials based on the remaining Carbon-14.