chemical tests Flashcards
what precipitate do iodide ions form
yellow
what colour do sodium ions go in flame tests
yellow
test for hydrogen
use a lit splint - gives a squeaky pop
test for oxygen
use a glowing splint - it will re-light it
test for carbon dioxide
limewater goes cloudy
test for chlorine
it turns moist litmus paper white
test for ammonia
turns damp red litmus paper blue
test for water using anhydrous copper sulfate
add it to sample - if water is present it will go from white to blue
physical test to see if water is pure
it will boil at 100 degrees
how to do flame test
- dip nichrome wire in hydrochloric acide to remove any impurities
- dip in substance
- put at cone of roaring blue flame
- observe colour
colours formed in flame test for positive ions for lithium
red
colours formed in flame test for positive ions for sodium
yellow
colours formed in flame test for positive ions for potassium
lilac
colours formed in flame test for positive ions for calcium
orange red
colours formed in flame test for positive ions for copper
blue green
for ammonium using sodium hydroxide solution
ammonia gas will form NH3
turns damp red litmus paper blue
tests for copper(ii), iron(ii) and iron (iii) using sodium hydroxide solution
copper(ii) - blue precipitate of copper hydroxide
iron(ii) - green precipitate of iron hydroxide
iron (iii), brown precipitate of iron hydroxide
