Group 2 and 7 Flashcards
what factors affect the ionisation energies of the alkali and alkaline earth metals?
size of the ion and charge of the ion
size of the ion ….. down group 2, why
increases, due to more shielding and less nuclear attraction
group 2 metal + water
metal hydroxide + hydrogen
group 2 metal + oxygen
metal oxide
group 2 metal + chlorine
metal chloride
reactivity of group 2 metal oxides …… down the group
increases
group 2 metal oxide + water
metal hydroxide
group 2 metal oxide + acid
salt + water
group 2 metal hydroxide + acid
salt + water
solubility of group 2 metal hydroxides ….. down the group
increases
magnesium hydroxide uses
as a laxative or for indigestion
solubility of group 2 metal sulphates ……. down the group
decreases
barium sulphate uses
barium meal to cause contrast in x rays
Thermal stability
a measure of resistance to thermal decomposition.
Thermal decomposition
when a substance breaks down when heated.
Polarizing power of a cation
its ability to pull the electrons from the anion into the space between the ions
What 2 things affect polarising power?
size of the ion, charge density
how does a cation polarise a carbonate
distorts the carbonate ion. This weakens the C-O bond
thermally stability of group 2 metal carbonates …….. down the group, why?
increases due to decreased charge density so decreased polarisation of the carbonate ion
thermal decomposition of a group 2 metal carbonate forms
metal oxide + carbon dioxide
fluorine properties
pale yellow gas at room temperature
chlorine properties
pale green gas at room temperature
bromine properties
brown liquid at room temperature
iodine properties
black/grey solid at room temperature
