Barrons SAT Subject Test Chemistry, 13th Edition

Carbon

monoxide

CO

1. Burn it and pass product through
   limewater, Ca(OH) 2.
   
   
   1. White precipitate forms, CaCO 3.
   
   
   
   

Hydrogen

H 2

1. Allow it to mix with some air, then
   ignite.
   
   
   1. Gas explodes.
   
   
   
   


2. Burn it—trap product.
   2. Burns with blue flame—product H 2 O turns cobalt
   chloride paper from blue to pink.

Hydrogen

chloride

HCl

1. Smell cautiously.
   
   
   1. Choking odor.
   
   
   
   


2. Exhale over the gas.
   2. Vapor fumes form.


3. Dissolve in water and test with
   litmus.
   3. Blue litmus turns red.


4. Add AgNO 3 to the solution.
   4. White precipitate forms.

Hydrogen

sulfide

H 2 S

1. Smell cautiously.
   
   
   1. Rotten egg odor.
   
   
   
   


2. Test with moist lead acetate
   paper.
   2. Turns brown-black (PbS).

Oxygen

O 2

1. Insert glowing splint.
   
   
   1. Bursts into flame.
   
   
   
   


2. Add nitric oxide gas.
   2. Turns reddish brown.

II. Identification of Some Negative Ions

Ion

Test

Result

Acetate

C 2 H 3 O 2 −

Add concentrated H 2 SO 4 and warm gently.

Odor of vinegar released.

Carbonate

CO 3 −

Add HCl acid; pass released gas through

limewater.

White, cloudy precipitate forms.

Chloride

Cl −

1. Add silver nitrate solution.
   
   
   1. White precipitate forms.
   
   
   
   


2. Then add nitric acid, later followed by
   ammonium hydroxide.
   2. Precipitate insoluble in HNO 3 but dissolves
   in NH 4 OH.

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