-- Core –

✔

Describe the structure of an atom in terms of a positively charged nucleus and negatively charged electrons in orbit around the nucleus.

Know how atoms may form positive ions by losing electrons or form negative ions by gaining electrons.

Describe the composition of the nucleus in terms of protons and neutrons.

State the relative charges of protons, neutrons and electrons as +1, 0 and –1 respectively.

Define the terms proton number (atomic number) Z and nucleon number (mass number) A and be able to calculate the number of neutrons in a nucleus.

Use the nuclide notation ${}_{\mathit{Z}}{}^{\mathit{A}}\mathit{X}$

Explain what is meant by an isotope and state that an element may have more than one isotope.

-- Extended –

✔

Describe how the scattering of alpha (α) particles by a sheet of thin metal supports the nuclear model of the atom, by providing evidence for:

a)a very small nucleus surrounded by mostly empty space

b)a nucleus containing most of the mass of the atom

c)a nucleus that is positively charged

Describe the processes of nuclear fission and nuclear fusion as the splitting or joining of nuclei, to include the nuclide equation and qualitative description of mass and energy changes without values.

Know the relationship between the proton number and the relative charge on a nucleus.

Know the relationship between the nucleon number and the relative mass of a nucleus.