84.4 Flashcards
what do we obsorve in reactions of oxides ith water
a solid would react to form a colourless solution
what is produced in reaction with of oxides in water
alkalis
what is the reaction for group 1 and group 2 metal oxides in water
group 1: M2O(s) + H2O(l) —> 2MOH(aq)
group 2: MO(s) + H2O(l) —-> M(OH)2 (aq)
the solubility of group 2 metal hydroxide increase
going down the group
what does the pH value of alkaline depend on
- the amount of oxide and water
2. the solubility of the hydroxides
what is the relationship between the pH value and the solubility of hydroxides
as the solubility increases the pH value increase
what is the test for carbon
lime water turns cloudy
what is the equation of the lime water test
CO2(g) + Ca(OH)2(Aq) —-> CaCO3(s) (insouble in water) + H2O (l)
What are the uses of Milk of magnesia
it neutralizes the HCl acid in the stomach helping with indigestion
what is the milk of magnesia
it is a solution made from saturated Magnesium hydroxide as well as an extra solid Magnesium hydroxide
what is the reaction that occurs in the stomach when we drink the milk of magnesia
2HCl + Mg(OH)2—-> MgCl2( + 2H2O
why isn’t drinking the milk of magnesia dangerous
because the solubility of the hydroxide is very low the concentration of the OH- ion is low not causing a risk
what can we observe in reactions of oxides and hydroxides with acids
- a white solid forms a coulourless solution
2. an increase in a thermometer since the reaction is exothermic
what is lime water also used for
to control the acidity (nitric acid) of a crop and increase the yield
what is the equation in this reaction
Ca(OH)2 + 2HNO3 —-> Ca(NO3)2 + 2H2O
what is the solubility trend for Group 2 sulfates
decreases down the group
what is the test for sulfate ions
add dilute nitric acid and barium nitrate solution to the sodium sulfate solution
why must be there H+ ions
to prevent the formation of a white participant of barium carbonate
why do we use barium ions to test for sulfates
because we need an insoluble salt and the solubility of group 2 sulfates go down the group
what is the equation for the sulfate test
Ba(NO3)2(aq) + Na2SO4(aq) —–> 2NaNO3(aq) + BaSO4(s)
what is a barium meal
it is barium sulfate used in hospitals to scan soft tissues
why is the barium meal safe to consume
because it is insoluble so the poisonous barium ions aren’t free to move around
