C9.1 Group 2 Elements Flashcards
What is the trend in atomic radius for the elements Mg–Ba?
Atomic radius increases down the group from Mg to Ba
This trend is due to the addition of electron shells.
What is the trend in first ionisation energy for the elements Mg–Ba?
First ionisation energy decreases down the group from Mg to Ba
This is because of increased atomic size and shielding effect.
How does the melting point of the elements Mg–Ba relate to their structure and bonding?
Melting point decreases down the group
However magnesium is the lowest.
Due to increased distance of cation and electrons
What happens when the elements Mg–Ba react with water?
They react to form hydroxides and hydrogen gas
The reactivity increases down the group.
What is the use of magnesium in the extraction of titanium?
Magnesium is used to reduce TiCl4 to titanium
This process is important for obtaining pure titanium.
What is the solubility of Mg(OH)2 in water?
Mg(OH)2 is sparingly soluble in water
This limits its use in certain applications.
How is Mg(OH)2 used in medicine?
Mg(OH)2 is used as an antacid
It neutralizes stomach acid.
What is the role of Ca(OH)2 in agriculture?
Ca(OH)2 is used to improve soil pH
It neutralizes acidic soils.
How do CaO or CaCO3 function in relation to flue gases?
They are used to remove SO2 from flue gases
This helps reduce pollution from industrial emissions.
What is the solubility of BaSO4 in water?
BaSO4 is insoluble in water
This property is significant in medical applications.
Why is BaCl2 solution used to test for sulfate ions?
BaCl2 reacts with sulfate ions to form BaSO4 precipitate
The test confirms the presence of sulfate ions.
Why is BaCl2 solution acidified when testing for sulfate ions?
It prevents the precipitation of barium carbonate
Acidification ensures accurate test results.
What is the significance of BaSO4 in medicine?
BaSO4 is used as a radiocontrast agent in imaging
It helps visualize internal organs during X-rays.
Titanium Dioxide (TiO2) into Titanium (IV) Chloride (TiCl4)
TiO2 + 2Cl2 + 2C -> TiCl4 + 2CO
Titanium (IV) Chloride (TiCl4) into Ti through Mg
TiCl4 + 2Mg -> Ti + 2MgCl2
How does CaO react with SO2 to prevent acid rain?
CaO + SO2 -> CaSO3
How does CaCO3 react with SO2 to prevent acid rain?
CaCO3 + SO2 -> CaSO3 + CO2
The reactions of metals and water gets more _ down the group
Vigorous
Magnesium reacts _ with steam
Vigorously
Solubility of group 2 hydroxides _ down the group
Increases
Solubility of group 2 sulfates _ down the group
Decrease
Describe structure and bonding in alkali metals
Giant lattice of mg cations
Form electrostatic attractions with delocalised electrons
