radiation

energy that comes from a source in the form of waves/rays that you cannot see

nucleus

center of an atom

half-life

the time it takes for half of a radioactive atom undergo radioactive decay

radioisotope

an element that has an unstable nucleus

radioactive decay

emission of energy as electromagnetic waves or as moving subatomic particles

Ionizing radiation is

considered the most harmful

During a nuclear reaction, unstable nuclei release ____ of energy

lots

During a nuclear reaction, unstable nuclei try and become _____ stable.

More

When is radiation most dangerous

when its ingested

Which ray has the least amount of penetrating power

alpha

Which ray is stopped by lead?

Gamma

⁴⁰ ₂₀Ca --> _____ + ⁰ _-1e

⁴⁰ ₂₁Sc

⁰ _-1e

beta

⁴ ₂He

Alpha

¹ ₀n

neutron

What is the half-life of the graph?

~3.4

What percentage was left after 11,400 years?

25%

How much time passed after 5% of the substance was left?

22,800 years

True or False.

As the number of half-lives increase, the total number of atoms that exist decreases.

False. They turn into a different substance but still exist.