Salt Analysis

A colourless and pungent-smelling gas that turns red litmus paper into blue.

• A. Ammonia, NH3

• B. Hydrogen Chloride, HCl

• C. Nitrogen Dioxide, NO2

• D. Sulphur Dioxide, SO2

A gas that rekindles a glowing wooden splinter.

• A. Nitrogen dioxide, NO2

• B. Hydrogen Chloride, HCl

• C. Hydrogen, H2

• D. Oxygen, O2

When applied with heat, this salt produces Carbon dioxide and metal oxide from decomposition.

• A. Sulphate salt.

• B. Nitrate salt

• C. Carbonate salt

• D. Chloride salt

What reagent is used to detect the presence of sulphur dioxide?

• A. Limewater

• B. Concentrated Ammonia

• C. Potassium permanganate solution

• D. Acidified potassium manganese (VII) solution

The following observation detects the presence of?

"A brown ring is obtained"

• A. Sulphate ion

• B. Nitrate ion

• C. Carbonate ion

• D. Chloride ion

A brown insoluble precipitate was produced after the addition of excess NaOH solution.

What cation was present in the salt?

• A. Cu2+

• B. Mg2+

• C. Fe2+

• D. Fe3+

NaOH and NH3 can be used as reagents for cation test. Why?

• A. Easy to synthesize

• B. Can combine with metal ions to produce soluble metal hydroxide that are easily observable.

• C. Can supply hydroxide ions needed to test metal ions.

• D. Generally safe and non-flammable.

Nessler's reagent is used to identify what cation?

• A. Fe2+

• B. Fe3+

• C. NH4+

• D. Pb2+

What was observed if Pb2+ ion is present using potassium iodide as a reagent?

• A. Dark blue precipitation

• B. Pale pink solution

• C. White precipitate

• D. Yellow precipitate that can appear and disappear depending on temperature.

A blue precipitate was observed after the addition of NaOH solution.

What is the inference?

• A. Copper ion is present

• B. Iron (II) ion is present

• C. Iron (III) ion is present

• D. Ammonium ion is present.