Group 2- The Alkaline Earth Metals Flashcards
What happens when group 2 elements react?
They lose electrons, forming positive ions (cations).
What is the trend in reactivity of group 2 elements and why?
Reactivity increases down the group as because there is more shielding between the nucleus and the outer electrons and the distance between the nucleus and the outer electron increases and therefore the force of attraction between the nucleus and outer most electrons is reduced. Also, the atomic radius increases, which is due to the extra shell of electrons for each element.
What ions do group 2 elements form?
2+ ions.
What happens when group 2 metals react with water?
They give a metal hydroxide and hydrogen.
What happens when group 2 metals react with oxygen?
You get solid white oxides.
What is thermal decomposition?
When a substance breaks down (decomposes) when heated.
The more thermally stable a substance is, the more heat it will take to break it down.
What are the products of group 2 carbonates decomposing?
The oxide of the element and carbon dioxide.
What is the trend in thermal stability as you go down group 2?
Thermal stability increases down the group.
As you go down group 2 the atomic radius…
increases, this is due to the extra shell of electrons for each element.
Why does an increase in atomic radius decrease first ionisation energy?
There is more shielding between the nucleus and the outer electrons and the distance between the nucleus and the outer electron increases and therefore the force of attraction between the nucleus and outer most electrons is reduced.
Give some examples of the uses of group 2 elements.
Limestone calcium carbonate CaCO3(s) making cement
Magnesium hydroxide- indigestion tablets and toothpaste to remove acidity.
Calcium hydroxide- solid is added to soil to reduce acidity
Calcium oxide- removal of impurities in the blast furnace
What are group 2 elements known as?
The alkaline earth metals
Describe one difference you might observe if strontium, instead of magnesium, was reacted with dilute hydrochloric acid.
Quicker OR more vigorous OR gets hotter
Describe what you would expect to see when magnesium ribbon is added to an excess of dilute hydrochloric acid.
Magnesium would dissolve.
Effervescence produced.
