Level 4: Inside the atom

Radiation and the atom · level 4 of 8 · rough age 11-12 (a guide for parents; anyone can start anywhere)

An atom is not a solid ball. It has a tiny heavy centre, the nucleus, made of protons and neutrons, with electrons around it. This level opens the atom up: what the nucleus is made of, why the number of protons decides the element, and how atoms of one element can still differ. It ends with what different kinds of argon and water tell us about the air Mars has lost.

Lesson	You will be able to
The nucleus	Describe the gold foil experiment and what it showed
Protons and neutrons	Say what is in a nucleus and what the atomic number counts
Electrons	Describe electrons, shells and ions
Isotopes	Say what an isotope is and give examples
Mass number and symbols	Read a nuclear symbol and count protons and neutrons
Isotopes on Mars	Explain how isotopes show that Mars lost its air and water

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