● Isotopes: differ in number of neutrons; ions: formed by electron gain/loss
● Charges of ions
○ Group 1 +, 2 2+, 3 3+; 5 3-, 6 2-, 7 -
○ Other “irregular” ions (including certain transition metals)
Metals and reactivity series
●
● Metals higher up in reactivity series react faster/more vigorously with water/(dilute)
acid
● Metals higher up in reactivity series displace metals lower down in series from their
oxides/(aqueous solutions of) salts
The periodic table
● Noble gases (Group 0) do not readily react as they have full outer electron shells
● Group 7 (halogens)
○ Chlorine
■ In solution (i.e.: in water) - pale green
■ In organic solvent (i.e.: containing carbon) - pale green
■ Halide ion form - Cl-
■ Na+ halide - colourless, soluble
■ Ag+ halide precipitate - white
○ Bromine
■ In solution - orange
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