Half-Life

Front

What is Half-Life?

Back

Half-Life is the time required for half of the radioactive atoms in a sample to decay.

Front

What percentage of the parent isotope remains after 1 Half-Life?

Back

50% of the parent isotope remains after 1 Half-Life.

Front

What percentage of the parent isotope remains after 2 Half-Lives?

Back

25% of the parent isotope remains after 2 Half-Lives.

Front

If you start with 100 grams of a radioactive substance, how much will remain after 1 Half-Life?

Back

50 grams will remain after 1 Half-Life.

Front

If the Half-Life of an isotope is 3 days, how much of a 12 gram sample will remain after 3 days?

Back

6 grams will remain after 3 days.

Front

What is the formula to calculate the remaining quantity of a substance after n Half-Lives?

Back

Remaining quantity = Initial quantity × (1/2)^n.

Front

What type of decay is alpha decay?

Back

Alpha decay is a type of radioactive decay in which an atomic nucleus emits an alpha particle (2 protons and 2 neutrons).

Front

What is beta decay?

Back

Beta decay is a type of radioactive decay in which a beta particle (an electron or positron) is emitted from an atomic nucleus.

Front

How does the Half-Life of a substance affect its stability?

Back

A shorter Half-Life indicates a less stable isotope, as it decays more quickly.

Front

What is the significance of Half-Life in carbon dating?

Back

Half-Life is used in carbon dating to determine the age of organic materials by measuring the remaining C-14.