Match each sulfur-related substance or allotrope in Column A with its corresponding physic… — JAMB UTME

Match each sulfur-related substance or allotrope in Column A with its corresponding physical or chemical property in Column B.

Rhombic sulfur ( $\alpha$ -sulfur)The stable octahedral crystalline allotrope of sulfur at room temperature below $95.6^\circ\text{C}$ .
Hydrogen sulfide ( $H_2S$ )A poisonous gas with a characteristic rotten-egg smell that turns moist lead(II) ethanoate paper black.
Sulfur(IV) oxide ( $SO_2$ )A gaseous reducing agent that turns acidified potassium dichromate(VI) solution from orange to green.
Plastic sulfurAn amorphous, rubber-like allotrope produced by rapidly cooling molten sulfur near its boiling point in cold water.

Answer

Rhombic sulfur matches the stable octahedral crystalline allotrope below

95.6^\circ\text{C}

; Hydrogen sulfide matches the poisonous gas with a rotten-egg smell that turns lead(II) ethanoate paper black; Sulfur(IV) oxide matches the gaseous reducing agent that turns acidified potassium dichromate(VI) solution from orange to green; Plastic sulfur matches the amorphous, rubber-like allotrope formed by rapidly cooling boiling sulfur in cold water.

Rhombic sulfur is the stable octahedral crystalline allotrope at room temperature (

< 95.6^\circ\text{C}

). Hydrogen sulfide is a toxic gas characterized by a rotten-egg odor and the ability to turn moist lead(II) ethanoate paper black due to

PbS

formation. Sulfur(IV) oxide is a gaseous reducing agent that changes orange acidified potassium dichromate(VI) to green chromium(III). Plastic sulfur is an amorphous, elastic allotrope made by quenching boiling sulfur in cold water.

Step-by-Step Solution

Identify the physical properties and structures of sulfur allotropes.

Rhombic sulfur (

\alpha

-sulfur) consists of octahedral crystals stable below

95.6^\circ\text{C}

, while plastic sulfur is formed by pouring boiling sulfur into cold water, producing an amorphous, rubbery solid.

Allotropes exhibit different structural arrangements and stability ranges based on temperature and cooling rate.

Analyze qualitative test reactions for hydrogen sulfide (

H_2S

) and sulfur(IV) oxide (

SO_2

Hydrogen sulfide gas has a distinctive rotten-egg odor and reacts with lead(II) ethanoate to precipitate black lead(II) sulfide (

PbS

). Sulfur(IV) oxide is a reducing agent that reduces orange

Cr_2O_7^{2-}

to green

Cr^{3+}

Each gas has unique chemical properties and reagent tests suitable for laboratory identification.

Key Concept

Physical properties of sulfur allotropes and chemical identification tests for hydrogen sulfide and sulfur(IV) oxide.

Question

Answer

Step-by-Step Solution

Key Concept

Common Mistakes

Topics

More questions from this topic