Chemistry: groups rates and energy

Elements in the same group have …

Similar chemical and physical properties

Properties of group 1 (alkali metals) (4)

• lower melting point compared to other metals

• Soft/ easy to cut

• Float on water/ low density

• Very reactive (especially with water)

Alkali metals react with oxygen → …

Alkali metals react with water → …

• metal oxide

• Metal hydroxide + hydrogen

In group 1 when you move down the group, it is _______ reactive as they get larger. Why?

• more reactive

• The electrons get further away from the nucleus → attracted less → easier to lose

Group 7 (halogens) are ______ with ______ boiling points

They are simple ionic/ covalent molecules

• non- metals

• Low

• Covalent

Many halogens exist as _______ molecules. (HINT Br²)

Diatomic

Halogens can be toxic and …..

They react with metals →

They react with hydrogen →

• Corrosive

• Metal halide salts

• Hydrogen halides (dissolve in H²0 → acidic solutions)

Halogens become _____ reactive moving down the group. Why?

• less

• As the halogens get bigger → attraction for outer shell electrons decreases → harder to gain electrons

Colours of halogens (group 7) - F² / Cl² / Br² / I² / At²

• yellow gas

• Green gas

• Orange/brown liquid

• Grey solid / brown solution

• Black solid

Displacement reactions show …

A more reactive halogen will replace a less reactive halogen in a compound - Cl² + NaBr →

Explain OILRIG in a redox reaction

Order of reactivity

Br² + NaCl

Oxidation is loss / reduction is gain of electrons