Atomic Structure Flashcards

Atomic Structure Key Concepts

• Protons are positively charged subatomic particles found in the nucleus of an atom.
• Neutrons are neutral particles, part of the nucleus, and do not have a charge.
• Electrons are negatively charged subatomic particles that orbit the nucleus.

Charges of Subatomic Particles

• Protons carry a positive charge.
• Neutrons possess no charge (neutral).
• Electrons have a negative charge.

Atomic Composition

• Protons and neutrons are the two substances located in the nucleus of an atom.
• The electron count in a neutral atom equals the number of protons.

Atomic Numbers and Mass

• The atomic number corresponds to the number of protons in an atom’s nucleus.
• Example: An atom with 35 protons will also have 35 electrons orbiting it.
• Atomic mass or mass number is the total number of protons and neutrons in the nucleus.

Calculating Subatomic Particles

• For an atom with an atomic number of 15, there will be 15 protons.
• The number of electrons equals the number of protons in a neutral atom.
• The number of neutrons can be calculated by subtracting the atomic number from the atomic mass.

Mass Number Examples

• An atom with 3 protons, 4 neutrons, and 3 electrons has a mass number of 7 (3 protons + 4 neutrons).
• For an atom with an atomic mass of 36 and an atomic number of 25, it has 11 neutrons (36 - 25 = 11).