Reactivity Trends Flashcards
What are group 2 metals called?
Alkaline Earth Metals
What are group 2 metals found as on Earth?
Stable compounds such as calcium carbonate
How does the electron configuration of Group 2 metals differ from that of a noble gas?
Two more electrons than the nearest noble gas
What is the most common type of reaction of group 2 elements?
Redox
What happens to a group 2 metal during a redox reaction?
Oxidised
Loses 2 electrons
Becomes a 2+ ion
Is group 2 an oxidising agent or reducing agent? Why?
Reducing agent- reduces another species by being oxidised
What is the reaction of a group 2 metal and oxygen?
Group 2 metal + oxygen = Metal Oxide
What happens when magnesium burns?
Magnesium burns with a bright light
What happens when a group 2 metal reacts with water?
Metal + Water = Metal hydroxide + Hydrogen
What happens to reactivity of group 2 metals with water down the group?
Reactivity increases down the group
What happens when a group 2 metal reacts with acid?
Metal + Acid = Salt + Hydrogen
What happens to reactivity in group 2 metals? Why?
Increases
Requires 2 ionisation energies.
Ionisation energy decreases because of greater shielding and atomic radii.
What is the reaction of group 2 oxides with water?
Group 2 oxide + water= metal hydroxide
Explain trend in solubility of hydroxides
Increases down the group
Resulting solutions contain more OH- ions
Explain trend in alkalinity of hydroxides
Solubility increases
More OH- ions
Increase in pH
Increase in alkalinity
What is the pH of magnesium hydroxide?
10
What is the pH of barium hydroxide?
13
How are group 2 compounds used in agriculture?
Ca(OH)2 are added to fields as lime to increase pH of acidic sols
What is the equation of group 2 compounds in agriculture?
Ca(OH)2 (s) + 2H+(aq) = Ca 2+(aq) + 2H20(l)
Which 2 group 2 compounds are used in medicine?
CaCO3
Mg(OH)2