Sodium sulfide - Na2S

What is Sodium sulfide?

Sodium sulfide is an inorganic chemical compound with the formula Na2S that has attained an important position in the organic chemical industry. It is a strong alkaline solution when exposed to moist air it smells like rotten eggs. Although the solid state is yellow in colour in solution it is colourless. Usually, it comes in the grades as “sodium sulfide flakes”.

IUPAC name – disodium sulfanide

Table of Content

Sodium sulfide Structure – Na2S

Sodium sulfide Na2S

Chemical Data on Sodium Sulfide-Na2S

Na2S Sodium sulfide
Density 1.86 g/cm³
Molecular Weight/ Molar Mass 78.0452 g/mol
Autoignition temperature > 480 °C (896 °F; 753 K)
Melting Point 1,176° C (2,149° F)
Chemical Formula Na2S

Physical Properties of Sodium sulfide – Na2S

Odour Odour of rotten eggs
Appearance Anhydrous yellow crystalline solids
Storage temp‎ 2-8°C
pH 10.4
Oxidation number -2
Solubility Insoluble in ether; slightly soluble in alcohol

Chemical Properties of Sodium sulfide – Na2S

    • Sodium sulfide dissolves in water to form its corresponding ions. The reaction is as below.

Na2S + H2O → 2Na+ + HS + OH

    • It can be easily oxidised when heated it forms sodium carbonate and sulfur dioxide.

2Na2S + 3O2 + 2CO2 → 2Na2CO3 + 2SO2

    • It reacts with sulphur forming polysulfides.

2Na2S + S8 → 2Na2S5

Uses of Sodium sulfide – Na2S

  • Used in water treatment as an oxygen scavenger agent and also used as a metal precipitant.
  • Used in the photographic industry to protect developer solutions from oxidation in textile industry as a bleaching agent.
  • Utilized in the production of elastic synthetic materials, sulfur colours and other substances.
  • Used primarily in pulp and paper industry in the craft process. It increases the selectivity of the sulfate cooking process and increase the rate of delignification.

Frequently Asked Questions-FAQs

Q1

1. What is sodium sulfide used for?

Sodium Sulfide is used primarily in the pulp and paper industry in the craft process. It increases the selectivity of the sulfate cooking process and increases the rate of delignification. It is used in the photographic industry to protect developer solutions from oxidation in the textile industry as a bleaching agent.

Q2

2. Is sodium sulfide harmful?

Sodium sulfide is a toxic, corrosive substance that causes severe burns on the mucous membrane.

Q3

3. What does sodium sulfide 1% do?

1% Sodium sulfide is used in the pulp and paper industry, water treatment, textile industry, and various chemical manufacturing processes including the production of rubber chemicals, sulfur dyes and oil recovery.

Q4

4. How do you make sodium sulfide?

In the laboratory, the salt can be prepared by reduction of sulfur with sodium in anhydrous ammonia, or by sodium in dry THF with a catalytic amount of naphthalene.

2 Na + S → Na2S.

Q5

5. Does sodium sulfide dissolve in water?

Yes, Sodium sulfide dissolves in water. It is slightly soluble in alcohol and insoluble in ether.

Test your knowledge on Sodium Sulfide

Comments

Leave a Comment

Your Mobile number and Email id will not be published.

*

*