Ai Test Flashcards
What is the flame test used for?
The flame test is used to identify positive ions.
How is the flame test conducted?
A clean nichrome wire is used to hold a small sample of test solid in the hottest part of a blue Bunsen burner flame.
What is the result for Lithium (Li+)?
Red
What is the result for Sodium (Na+)?
Yellow
What is the result for Potassium (K+)?
Lilac
What is the result for Calcium (Ca2+)?
Orange-red
What is the result for Copper (Cu2+)?
Blue-green
What is the result for Copper (Cu2+) in precipitation?
Blue precipitate
What is the result for Iron (Fe2+) in precipitation?
Dirty green precipitate (goes red-brown over time)
What is the result for Iron (Fe3+) in precipitation?
Red-brown precipitate
What is the result for Ammonium (NH4+)?
Only the ammonium ion will form ammonia in this test and turn the red litmus paper blue.
What is the test for negative ions?
Precipitation with silver nitrate and acidified barium nitrate/chloride.
How do you test for Chloride (Cl-)?
Add nitric acid then silver nitrate.
What is the result for Chloride (Cl-)?
White precipitate
What is the result for Bromide (Br-)?
Cream precipitate
What is the result for Iodide (I-)?
Yellow precipitate
What is the result for Sulfate (SO4 2-)?
A white precipitate (of BaSO4) forms.
How do you test for Carbon Dioxide (CO2)?
Pass it through limewater.
What is the result for Carbon Dioxide (CO2)?
Change from colorless to cloudy in the limewater as CO2 is evolved.
What is the test for Hydrogen gas?
A test tube of hydrogen will burn with a squeaky pop when a lit splint is applied.
What is the test for Oxygen gas?
A test tube of oxygen will rekindle the flame in a glowing splint.
What is the test for Ammonia gas?
Ammonia will make damp red litmus turn blue.
What is the test for Chlorine gas?
Damp blue litmus paper will change to red then white.
What is the test for Water?
Anhydrous copper(II) sulfate solid will change from white to blue in the presence of water.
What is the boiling point of pure water at atmospheric pressure?
100 °C
