Describe the model of the atom that Dalton developed in the early 1800s.

Explain how the model of the atom changed following the series of experiments that took place between 1897 and 1911.

How many protons, neutrons and electrons are in the following atoms and Ions?
(a) Lithium-7, (b) Sodium-24,
(c) Fluorine-19, (d) Iron-56,
(e) Potassium, (f) Calcium (2+)
(g) Fluorine (-), (h) Oxygen (2-)

Write down symbols for the following atoms and ions.
(a) Atom: P=13, N=14, E=13
(b) Ions: P=16, N=16, E=18

Explain why the same products would be formed when both carbon-12 and carbon-13 are combusted in oxygen.

Calculate the relative atomic mass of the following. (4sf)
(a) Boron containing 19.77% 10B and 80.23% 11B
(b) Silicon, containing 92.18% 28Si, 4.70% 29Si and 3.12% 30Si.
(c) Chromium, containing 4.31% 50Cr, 83.76% 52Cr, 9.55% 53Cr and 2.38% 54Cr.