SODIUM SULFIDE Na2S

Properties of sodium sulfide Na2S:

White, melts without decomposition, heat-resistant. Anhydrous Na2S powder is pyrophoric in dry air. Readily soluble in water (strong hydrolysis on the anion). High reactivity, in moist state oxidized by oxygen of air, attaches sulfur. Decomposes by acids. Typical reductant.


Molar mass g/mol 78.05
Density g/cm3 1.86
Melting point °C 1180

Obtaining sodium sulfide Na2S:

2 Na + E = Na2E (t > 130° С, E = S, Se, Те)

2 Na + nS = Na2(Sn) (-40° С, in the liquid NH3, n = 1, 2, 4, 5).

Na2SO4 + 4H2 = Na2S + 4H2O (550-600°C, catalyst Fe2O3).

H2S + NaOH (diluted) = NaHS + H2O

H2S + 2NaOH (diluted) = Na2S + 2H2O.


Reactions with sodium sulfide Na2S:

Na2S·9H2O = Na2S + 9H2O (15-35°C; conc. H2SO4, P4O10).

Na2S (diluted) + 8H2O = 2[Na(H2O)4](+) + S(2-).

S(2-) + H2O ↔ HS(-) + OH(-).

Na2S + 2HCl (diluted) = 2NaCl + H2S↑.

Na2S + 3H2SO4 (diluted) = 2NaHSO4 + SO2↑ + S↓ + 2H2O

Na2S + 4HNO3 (diluted) = 2NaNO3 + 2NO2↑ + S↓ + 2H2O.

Na2S (solution) + NaOH → O2(air), solid S(colloid), Na2Sn.

Na2SO3S + Na2S (solid) + 2O2 = Na2SO4 (t > 400°C)

Na2S + H2S (saturated.) = 2NaHS.

Na2S (solution) + (n - 1)S = Na2(S4)  [boiling].

Na2S + S = Na2(S2) (600°C).

Na2S + 3S = Na2(S4) (400°C).

Na2S + 4S = Na2(S5) (200°C).

Na2S + CaCO3 = Na2CO3 + CaS (1200°C).

Na2S (diluted) + Na2SO3 (diluted) + I2 = Na2SO3S + 2 NaI.

Na2S + 4H2O2 (conc.) = Na2SO4 + 4H2O.


 

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