Group 2 Flashcards
In group 2, what is the trend in reactivity going down the group?
It increases
In group 2, explain the trend in reactivity going down the group
The 2 outer electrons are further away from the nucleus and there is more electron shielding so less attraction and less energy is needed to remove them (so higher reactivity)
Reaction between group 2 metal and oxygen
2M + o2 ———-> 2MO
What is produced when a group 2 metal is reacted with oxygen?
Metal oxide
Reaction between group 2 metal and water
M + 2H2O ———-> M(OH)2 + H2
What is produced when a group 2 metal reacts with water?
Metal hydroxide (a base making the solution more alkaline) and hydrogen
Outline the reactivity of magnesium
Reacts slightly with cold water and more vigorously with steam
Ca(OH)2 is a…
White precipitate
In group 2, what happens going down the group with reactions with water?
Hydroxides produced become more soluble as more OH- ions are released into the solution which becomes more alkaline
What happens when a group 2 metal reacts with a dilute acid?
Forms a salt and hydrogen
The equation for when a group 2 metal reacts with a dilute acid
M + 2HCl ———-> MCl2 + H2
What is calcium hydroxide used for?
To neutralise acids as if soils are too acidic, then crops will not grow well so they increase soil pH to the desired value
What is calcium carbonate or magnesium hydroxide used for?
As antacids which are used to treat indigestion - stomach acid in the oesophagus causing inflammation of tissues causing a pain called acid indigestion - and they neutralise this acid and remove the pain