C4.1

Question 1

Alkali metals

Answer 1

Gets softer as you go down the group
Density increases
Melting point decreases
Reactivity increases

Question 2

Halogens

Answer 2

Density increases
Melting points and boiling points increase
Reactivity decreases

Question 3

Displacement

Answer 3

A more reactive halide displaces a less reactive one from a compound - leaving the displaced compound as a diatomic compound by itself at the end of the equation (colour of solution)

Question 4

Colour of halogens

Answer 4

Fluorine- green gas
Chlorine - pale yellow gase
Bromine - yellow brown liquid
Iodine - dark grey crystalline solid
Astatine - radioactive (metallic properties)

Question 5

Noble gases

Answer 5

Attractive forces between atoms gets stronger (boiling points increase)
Density increases (tho very low - they’re in the gas state)

Question 6

Transition metals

Answer 6

Harder (higher density and melting point)
Form many types of ions
Coloured ionic compounds
Less reactive than alkali metals
Good catalysts

Question 7

How do metals react with water and dilute acids?

Answer 7

More easily they form positive ions the more reactive the metal
Metal only reacts with water or dilute acid if it is MORE REACTIVE THAN HYDROGEN (copper, silver, gold, platinum)
React with water - metal hydroxide + hydrogen
React with acid - salt + hydrogen

Question 8

What does rate of reaction tell you?

Answer 8

More reactive the metal -> greater the rate of hydrogen production and this means more vigorous bubbling (eye protection should be worn)
Add 2cm3 of water into test tube and add a small piece of metal - notice rate of bubbling and if no bubbling occurs then gently warm water to see if bubbling increases (repeat process with acid/different metals)
Not boil water or acid because it would bubble if boiled so unable to differentiate between bubbling of metal reaction or of solution and unsafe to boil acid

Question 9

Metal displacement

Answer 9

More reactive metal can displace a less reactive metal from solutions of its compounds
Examples of redox reactions
Cu (s) + 2AgNO3 (aq) -> Cu(NO3)2 (aq) + 2Ag (s)

Question 10

General trends

Answer 10

Elements in group 9 are unreactive
Metals in group 1 and 2 more reactive down the group and more reactive than transition metals
Non metals in group 7 get less reactive down the group
Non-metals + non-metals form covalent
Metals + non-metals from ionic