PSF Unit 7 Atoms Review

The nucleus of an atom is made up of

• Protons and Neutrons.

• Protons and Electrons.

• Neutrons and Electrons.

Which particle orbits the nucleus in an atom?

• electrons

• protons

• neutrons

Electrons are NOT

• negatively charged particles.

• responsible for the chemical properties of an atom.

• responsible for the identity of an atom.

Neutrons are __________ charged particles.

• negatively

• positively

• neutral

Protons are __________ charged particles.

• neutral

• negatively

• positively

A carbon atom has an atomic number of 6 and a mass number of 12. How many protons does it have?

• 6

• 12

• 18

A chlorine atom has a mass number of 35 and an atomic number of 17. How many neutrons does it have?

• 17

• 18

• 35

Unstable isotopes can become stable by

• releasing particles and/or energy.

• changing their name.

• doing nothing because they can't ever become stable.

When an unstable isotope releases a particle to become more stable it is called

• Radioactive Decay.

• Neutrality.

• Letting Go.

When an atom releases a helium atom it is called

• an alpha particle

• a beta particle

• gamma rays