C12 Flashcards
flame test for potassium
lilac flame
flame test for lithium
crimson flame
flame test for sodium
yellow flame
flame test for calcium
orange flame
flame test for copper
green flame
adding sodium hydroxide to metals
The hydroxides of metals that have ions with 2+ or 3+ charges are insoluble in water. When you add sodium hydroxide to solutions of these ions, a precipitate of the metal hydroxide forms
aluminium + sodium hydroxide
White precipitate formed.
When excess sodium hydroxide is added, the white precipitate of aluminium hydroxide dissolves, showing aluminium ions are present.
calcium + sodium hydroxide
White precipitate formed.
magnesium + sodium hydroxide
White precipitate formed.
copper(II) + sodium hydroxide
Blue precipitate of copper (II) hydroxide appears.
iron (II) + sodium hydroxide
Green precipitate of iron (II) hydroxide produced.
iron (III) + sodium hydroxide
brown precipitate of iron (III) hydroxide is formed
sulfate formula
SO4
sodium hydroxide formula
NaOH
test for carbonate ions
Add dilute hydrochloric acid to the substance to see if it fizzes.
If it fizzes and the gas produced turns limewater cloudy, the substance contains carbonate ions.
Test for halide ions.
Add dilute nitric acid then silver nitrate solution.
Chloride ions give a white precipitate.
Bromide ions give a cream precipitate.
Iodide ions give a pale yellow precipitate.
Test for sulfate ions.
Add dilute hydrochloric acid and then barium chloride solution.
If a white precipitate froms, sulfate ions are present.
Pure substance
Made of only 1 element or compound
Test for the prescience of water
Turns white anhydrous copper surface blue
Test for pure water
Boiling point exactly 100 degrees Celsius and melting point exactly 0 degrees Celsius
Impurities melting point
Impurities lower the melting point of a substance and raise its boiling point
Formulation
A mixture that has been designed to produce a useful product, each chemical in the mixture has a specific purpose, chemicals are mixed in set proportions to give the product its requires properties
Paints contain
Paint is a formulation Contains: Pigment-colour Binder- helps paint attach to object Solvent- helps pigment and binder spread well during painting
Formulation e.g.s
Fuels, alloys, fertilisers, cleaning agents, paints, medicines, cosmetics and food products.
Paper chromatography
Mobile phase is solvent
Stationary phase is paper
