Chemical and Physical tests Flashcards
How do you carry out a flame test?
- dip the nichrome wire into hydrochloric acid to clean it
- put the nichrome wire into the sample solid/liquid
- place into blue roaring flame
- describe the colour
in a flame test what do you see when lithium ions are present?
red
in a flame test what do you see when sodium ions are present?
yellow
in a flame test what do you see when potassium ions are present?
lilac
in a flame test what do you see when calcium ions are present?
orange - red
in a flame test what do you see when copper ions are present?
blue - green
what is the test for hydrogen?
lit splint causes a squeaky pop if hydrogen is present
what is the test for oxygen?
glowing splint relights if oxygen is present
what is the test for carbon dioxide?
bubble through limewater - if present limewater goes milky white
what is the test for ammonia (NH3)?
dam red litmus paper goes blue
what is the test for chlorine?
damp limbs paper bleaches white
how do you carry out the halide tests?
- add nitric acid to remove any carbonate ions
- add sliver nitrate and a precipitate will form
in the halide tests what colour will the precipitate go if chloride ions are present?
white
in the halide tests what colour will the precipitate go if bromide ions are present?
cream
in the halide tests what colour will the precipitate go if iodide ions are present?
pale yellow
how do you test for carbonate ions?
add hydrochloric acid and a gas will form
bubble the gas through limewater
a carbonate will produce limewater and CO2. It will go cloudy white.
what is the chemical test for water?
add to anhydrous copper sulphate - will go blue
what is the test for alkenes?
bromine water will go orange to colourless
what is the physical test for water?
water freezes at 0 degrees.
water boils at 100 degrees
how do you carry out the metal cation tests?
add sodium hydroxide
identify the precipitate
in the metal cation tests what colour will the precipitate be if copper ions are present?
blue
in the metal cation tests what colour will the precipitate be if iron (III) ions are present?
orange/brown
in the metal cation tests what colour will the precipitate be if iron ions are present?
green
what is the sulphate test?
- add barium chloride
- white precipitate of barium sulphate will form is sulphate ions present.
