8.1 - 8.3 Flashcards
What ions do group 2 elements form when they react and how
- +2 ions by loosing 2 electrons
What is the electron configuration that all group 2 metals have
- s^2
What happens to the atomic radius as we go down group 2 and why
- IT INCREASES as there are extra shells added
What happens to ionisation energy as you go down group 2 and why
- IT DECREASES
SHIELDING: - extra shells so more shielding so a weak attraction between the nucleus and the electrons so easier to remove outer electrons
ATOMIC SIZE:
- the atom is radius also increases as the atom is getting bigger so the outer electron is further away from the nucleus which also weakens the attraction making the outer electron easier to remove
NUCLEAR CHARGE:
- there is an increase in the number of protons as you go down but shielding and atomic size override this
What happens to reactivity as you go down group 2 and why
- IT INCREASES
- because the atom gets larger and the electron is further away from the nucleus
- easier to remove so there are more reactive
- also there is more shielding
What are the products when group 2 elements react with water
- metal hydroxides + H2 (g)
How does Mg react with cold water
- slowly
How does Mg react with steam and what does it produce
- vigorously
- MgO
What are the products when group 2 elements react with oxygen
- metal oxides
What colour are group 2 oxides
- white solids
What product do you get when you react a group 2 oxide with water
- metal hydroxides
Describe the reactivity of MgO with water
- reacts very slowly
- hydroxide barely dissolves
What happens to the group 2 metal oxides reaction with water as you go down the group and why
- becomes more strongly alkaline
- as the hydroxides becomes more soluble
What are group 2 oxides and hydroxides
- bases
As group 2 oxides and hydroxides are bases what can they do
- neutralise acids
What is the neutralisation reaction of CaO with HCl
CaO(s) + 2HCl(aq) —> CaCl2(aq) + H2O(l)
What is the neutralisation reaction of Ca(OH) with HCl
Ca(OH)2 (s) + 2HCl(aq) —> CaCl2(aq) + 2H2O(l)
What are uses of group 2 compounds
- acidic soils= Ca(OH)2 (slaked lime) is used to neutralise acid is soils
- antacids= Mg(OH)2 is used to neutralise excess stomach acid
What is the ionic equation for neutralisation
H+(aq) + OH-(aq) —> H2O(l)
What are the halogens
- group 7 elements
What colour is fluorine and what state is it in
- pale yellow
- gas
What colour is chlorine and what state is it in
- pale green
- gas
What colour is bromine and what state is it in
- browny orange
- liquid
What colour is iodine and what state is it in
- grey
- solid
What are group 7 elements
- diatomic
State and describe the boiling point of group 7 as you go down
- INCREASES
- because the London forces increase due to increase in the atomic size and relative mass of the atom
State and describe the trend in electronegativity as you go down group 7
- DECREASES
- because the larger the distance between the nucleus and the electron the more shielding there is
What are displacement reactions
- where a halogen that is more reactive will displace a halogen that is less reactive