4.13 - Reactions of the Group 2 Oxides and Hydroxides, and Trends in Solubility Flashcards
What type of oxide do group 2 metals form?
Basic oxides
What does this mean?
They can react with water to form alkalis
What is the general equation for these reactions?
MO(s) + H2O(l) -> M(OH)2(aq)
What is the trend in solubility of hydroxides?
Increases down the group
How do you test for carbon dioxide?
By using limewater
What forms in this test?
A white precipitate
How can lime be used in agriculture?
Using it to neutralise the acidic soil
Which sulfates are soluble, and which are insoluble?
Magnesium is soluble, calcium is slightly soluble, strontium and barium are insoluble
What is the test for sulfate ions?
Addition of barium ions
What has to be added first?
Dilute nitric or hydrochloric acid
Why?
To stop barium carbonate forming
What is a barium meal used for?
Helping soft tissue to show up on X rays
Why is it safe?
Because barium sulfate is insoluble
