group 2, group 7 and ions tests Flashcards
what are group 2 elements called?
Alkaline earth metals
what does ‘alkaline in alkaline earth metals mean?
the oxides of these metals releases OH- ions in solution
what does ‘earth’ in alkaline earth metals mean?
Very abundant in the earths crust
what structure do all gorup 2 elements have?
All Group 2 metals have the giant metallic lattice structure
how do group 2 metals conduct electricity?
Metals conduct electricity when solid or liquid because the electrons are delocalised and can move
why do group 2 metals have High Melting and Boiling Points
It takes a lot of energy to break the strong electrostatic attraction between the ions and the delocalised electrons
give the general equation for metals + oxygen
2M(s) + O2(g) —–> 2MO(s)
give the general equation for metals + water
M(s) + 2H2O(l) —> M(OH)2(s) + H2(g)
give the general equation for metals + steam
M(s) + H2O(g) —–> MgO(s) + H2(g)
give the general equation for metals + an acid (use H2SO4)
M + H2SO4 —-> MSO4 + H2
What is the reactivity of metals like down a group?
More Reactive Down the Group
What do metals get more reactive down the group/why does ionisation energy decrease down the group?
- There are more shells of electrons.
- Therefore, the outer electrons are further from the nucleus and more shielded.
- So the nuclear attraction for the outer electron is less.
- The outer electrons are more easily lost.
What is a common use for calcium oxide/hydroxide?
Neutralisation of acidic soils
what is a common ise for magnesium hydroxide or calcium carbonate?
Neutralises stomach acids when you have a stomach ache
What is produced when a metal oxide reacts with water?
metal hydroxide is only produced
what occurs to the pH of hydroxides down the group?
increases
ACID + BASE —–>
SALT + WATER
ACID + CARBONATE ——>
SALT + WATER + CARBON DIOXIDE