The Structure of the Atom (AQA GCSE Combined Science: Trilogy): Revision Note Exam code: 8464

The Structure of the Atom (AQA GCSE Combined Science: Trilogy): Revision Note

Exam code: 8464

Relative electrical charges of subatomic particles

  • Protons, neutrons and electrons are the subatomic particles that make up atoms

Relative electrical charges

Atomic Structure Mass and Charge Distribution

The mass of the atom is concentrated in the positively charged nucleus which is attracted to the negatively charged

  • Each of the subatomic particles has a different electric charge, which is summarised in the following table

Sub-Atomic Particle Comparison (Charge) Table

Particle

Charge

Proton

+1

Neutron

0 (neutral)

Electron

-1

  • Atoms are neutral overall

    • Even though they contain charged subatomic particles, the charges cancel each other out in an atom

  • Since the charge on a proton is +1 and on an electron is -1, then the number of protons must be the same as the number of electrons for the charges to cancel each other out and produce a neutral atom

Examiner Tips and Tricks

Protons are Positive sub-atomic particles while Neutrons are Neutral. That leaves the electrons which must therefore be negative.



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