Inorganic - Group 2 Flashcards
what occurs when group 2 metals react?
lose 2 electrons, forming 2+ ions, achieving a full outer shell
what is the trend in atomic radius going down group 2? why?
- increases
- due to additional electron shells
what is the trend in reactivity down group 2? why?
- increases
- because increased shielding means the outer electrons are lost more easily
what is the trend in first ionisation energy down the group? why?
- decreases
- due to greater atomic radius and increased shielding, reducing the electrostatic force
what is the trend in melting point going down group 2?
- decrease
- because group 2 elements are metallic so the larger the ions, the weaker the electrostatic force as it has to act over a greater distance
in what kind of reaction do group 2 metals react with water?
redox reactions
what are the products of a group 2 metal’s reaction with water?
metal hydroxide and hydrogen
how does magnesium react with liquid water?
very slowly
what is the trend in solubility of group 2 hydroxides down the group?
increases
how is magnesium hydroxide used in medicine?
it is an antacid as it is alkaline and so can neutralise acids, treating heartburn
how is magnesium hydroxide used in agriculture?
to neutralise acidic soils
what is the trend in solubility of group 2 sulphates going down the group?
decreases
what is the least soluble group 2 sulphate?
barium sulphate
how is barium sulphate used in medicine?
- barium meals
- medical tracer that allow internal tissues and organs to be imaged during x-rays
why is barium sulphate safe for use as barium meals in medicine?
it is toxic if it enters the bloodstream but this cannot happen as it is insoluble
