Radioactivity

A radioactive atom is any atom that contains an unstable _____.

• energy level

• nucleus

• orbital

• electron

What is the mass number of this isotope?

• 131

• 53

• 184

• 78

An alpha particle is made up of

• 2 protons and 4 neutrons

• 1 proton and 1 neutron

• 2 protons and 2 neutrons

• 4 protons and 2 neutrons

When a substance undergoes beta decay

• The atomic number increases by 1

• The atomic number decreases by 2

• The atomic number does not change

When a nucleus undergoes nuclear decay by gamma rays, the atomic number of the element....

• remains the same
•   decreases by one.
• increases by one.
• increases by two.

In the symbol ²⁰⁶₈₂Pb what does 206 stand for?

• Mass number
• Atomic number
• Atomic mass
• Number of protons

The three types of nuclear radiation in increasing order of penetrating power are ____.  

• alpha, beta, gamma 

• X ray, beta, gamma
• alpha, gamma, beta 
• X ray, gamma, beta 

What is an isotope

• An atom with the same number of neutrons different number of protons

• An atom that has lost or gained an electron

• An atom with the same number of protons, different number of neutrons

• An atom with the same number of electrons and different neutrons

The diagram shows radioactive waste thrown into the ocean that causes mutations in aquatic life. Why does this happen?

• Radiation can damage cells & DNA

• The energy released heated the seawater.

• The fish used the radiation to treat cancer.

Radiation therapy can be used to treat what condition?

• acne

• cancer

• indigestion