Atoms & Ions
Physics: Edexcel IGCSE, topic 7.1.7
Atoms and Ions
Atoms have no overall electrical charge. When an atom becomes charged by gaining or losing electrons it becomes an ion.
Atoms are neutral
- In an atom, the number of electrons is equal to the number of protons in the nucleus.
- Atoms have no overall electrical charge.
Positive ions
- Atoms turn into positive ions if they lose one or more outer electrons.
Negative ions
- Atoms turn into negative ions if they gain one or more electrons.
Test yourself on Atoms & Ions
How does the nucleus of an atom change when it gains electrons?