Qualitative Analysis and Cation Tests

This set of flashcards covers key concepts in qualitative analysis flame tests and cation tests, including the colors and observations associated with various cations and anions.

What flame color does Li+ produce in a flame test?

Red (scarlet)

What flame color is observed for Na+ in flame tests?

Yellow/orange

In a flame test, what color does K+ produce?

Lilac

What is the flame color for Ca2+?

Brick red

What flame color is produced by Sr2+?

Red (crimson)

What flame color does Ba2+ exhibit in a flame test?

Apple-green

What do sulfate ions (SO4 2-) produce when tested with Ba2+?

White precipitate (ppt)

What reaction indicates the presence of carbonate ions (CO3 2-)?

Fizzes with any acid, producing CO2 and limewater.

What color precipitate is observed with Mg2+ when testing for hydroxide OH-?

White precipitate (ppt)

What precipitate forms when Cl- is tested with AgNO3?

White precipitate (ppt)

What color precipitate do Br- ions give when tested with AgNO3?

Cream precipitate (ppt)

What color precipitate do I- ions form when reacted with AgNO3?

Yellow precipitate (ppt)

What is the observation for Mg2+ in Cation tests with SO4 2-?

White precipitate (ppt)

What happens when Ba2+ is tested with carbonate CO3 2-?

White ppt.

What is the result for Ca2+ with hydroxide OH-?

Thin white precipitate (ppt)

What happens when Al3+ is tested with NaOH?

Colorless solution, white ppt which redissolves in excess.

What color precipitate do Pb2+ and Cl- form?

White precipitate (ppt)

How does Cu2+ with hydroxide react?

Blue precipitate which does not redissolve in excess.

What color precipitate does Fe2+ form with hydroxide?

Grey-green ppt that does not redissolve.

What happens when Cr3+ is tested with NaOH?

Green solution, grey-green ppt which redissolves.

What is the outcome when Fe3+ reacts with NH4OH?

Orange-brown ppt which does not redissolve in excess.

What do Pb2+ ions form when tested with I-?

Bright yellow ppt.

How is Zn2+ identified using NaOH?

Colorless solution, white ppt which redissolves in excess.

What color does the Fe2+ ppt turn at the top over time?

Turns brown.

What behavior is confirmed when a white ppt with Pb2+ shows redissolving in excess NaOH?

These metals are amphoteric.

What observation indicates that certain metals are not amphoteric?

A ppt that does not redissolve in excess.

What color is the initial precipitate observed for Cu2+ ions with hydroxide?

Blue ppt.

Which group has all soluble compounds?

Group 1 compounds.

What appearance is noted for Sr2+ with hydroxide?

Thinner white ppt.

What is unique about Be in Group 2 tests?

It is ignored due to anomalous behavior.

What happens to the initial white precipitate of Pb2+ when tested with excess NaOH?

It redissolves.

Which cations give a grey-green precipitate with hydroxide?

Fe2+ and Cr3+.

What ions will give a white ppt and a brown solution when testing Cu2+ with iodide?

Cu2+ with I- gives CuI (white) and iodine (brown solution).

What type of precipitate does Ba2+ give when tested with hydroxides?

No ppt.

For which ion does the carbonate test fizzes with acid?

Carbonate ions (CO3 2-).

What does a 'fizz' indicate in a carbonate test?

Carbon dioxide (CO2) production.