C2 - Salts And Precipitation Reactions Flashcards
What are salts?
Ionic compounds that can be insoluble or soluble in water
How are salts neutrally charged?
They are composed of related numbers of cations and anions
What substances are mainly soluble in water?
All nitrates
Most chlorides, bromides, iodides and sulphates
Sodium carbonate and sodium hydroxide
Potassium carbonate and potassium hydroxide
Ammonium carbonate and ammonium hydroxide
What substances are insoluble in water?
Most carbonates and hydroxides
Silver chloride, silver bromide and silver iodide
Lead chloride, lead bromide and lead iodide
How do you produce a pure dry sample of an element?
Use the two substances provided and add them together to form a precipitate, then filter the precipitate by draining the rest of the liquid and leave to dry to obtain a pure dry sample of the two elements
If an element is insoluble what does this mean?
It is unable to be dissolved in water and therefore a precipitate is formed
If an element is soluble what does this mean?
It is able to be dissolved in water and therefore does not form a precipitate
Stage two facts about barium sulphate that makes it safe to use for x rays…
It is opaque to x rays and therefore shows up clearly
It is safe to use although barium salts are toxic it’s insolubility prevents it from being able to enter the bloodstream
What colour would sodium show in a flame test?
Yellow
What colour would potassium show in a flame test?
Lilac
What colour would calcium show in a flame test?
Red
What colour would copper show in a flame test?
Green/Blue
