Group 2 Flashcards
What is the trend in atomic radius as you go down a group?
Atomic radius gets larger due to extra electron shells being added as you go down the group
What is the trend in ionisation energy in group 2 elements
G2 elements have 2 electrons in their outer shells so they can lose their 2 outer electron to form 2+ions , their ions then have a noble gas configuration
What is the trend in first ionisation energy down G2?
Decreases as each element down the group has an extra electron shell in comparison to the previous one, outer electrons also further distance away from nucleus which greatly reduces the nucleus’s attraction. And these combined factors make the ionisation energy decrease significantly
What is the trend in reactivity down group 2?
Reactivity increases down a group because atomic radius increases making it easier for them to lose e
What is the trend in melting point down a group
Melting point decreases because G2 have a metallic structure with positive ions and a sea of delocalised electrons, as metal ions get bigger, the number of delocalised e per atom doesn’t and neither does the charge so it takes less energy to break the bonds
What is the anomaly with the trend in melting point for G2?
Magnesium because the crystal structure changes
What are the trends in reaction with water for G2?
When G2 elements react they are oxidised from a state of 0 to +2 forming metal 2+ ions , these then react with water ( 2 ) and form a metal hydroxide (m(oh)2) and hydrogen . As ionisation energy decreases the reactivity increases
What does the solubility of G2 compounds rely on/what is the trend ?
Depends on the anion in the compound generally compounds of G2 elements contain singly charged negative ions i e oh , that increases solubility down the group whereas compounds that contain doubly charged negative ions decrease in solubility down the group
What is barium useful for?
It’s insoluble so its useful for finding broken bones but they pass through soft tissue like the digestive system so they dont show up on conventional x rays . Barium sulfate is the only compound usable for this though as barium ions are toxic and barium sulfate forms a suspension rather than a solution
How is titanium extracted
Magnesium is part of the process where :
TiCl4 (g)+2Mg(l)-> Ti(s)+2MgCl2(l)
Process of removing sulfur dioxide from flue gases?
CaO(s)+2H2O(l) + SO2(g)-> CaSO3(s) +2H2O(l)
CaCO3(s)+2H2O(l)+SO2(g)-> CaSO3(s) +2H2O(l)+CO2(g)
