Atoms and Molecules

All matter is made of extremely tiny particles called___________________

• atoms
• bits
• dust
• molecules

The center of an atom is called the______________.

• middle
• top
• nucleus
• electron

Atomic nucleus is made up of ____________

• protons and electrons
• protons only

• neutrons only

• protons and neutrons

Proton number is

• Number of particles in an atomic nucleus

• Number of protons in an atomic nucleus

• Number of positive charge on ion

• Number of protons and neutron in an atomic nucleus

Proton number also known as ____________

• Nucleon number

• Atomic symbol

• Atomic mass

• Atomic number

Define nucleon number.

• Number of neutrons in an atomic nucleus

• Number of nucleons in an atomic nucleus

• Number of protons and neutrons around a nucleus

• Total number of protons and neutrons in an atomic nucleus

Isotopes are atoms of the same element that have same number of protons but different _________

• number of electrons

• number of neutrons

• atomic number

• neutron number

If an atom has 5 protons and 3 neutrons, what is its atomic number?

• 5
• 2
• 8
• 3

What is the atomic mass of an atom?

• number of protons in the atom
• number of protons and neutrons in the nucleus
• how much it weighs
• number of electrons in the atom

Which subatomic particle of an atom has a positive charge?

• proton
• neutron
• electron
• nucleus