HNCS - THIOCYANIC ACID

Properties of thiocyanic acid:

It is colorless viscous high-polarity liquid, white solid substance. There is at very low temperatures. It has the structure of (H-N=C=S) with possible admixture tautomer (H-S-C≡N). When the temperature rises to -90... -85° C, forms a white polymer. Stable in a dilute solution. Shows strong acidic properties, it is neutralized by alkalis. At concentration of the solution it is decomposes. It reacts with acids, hydrogen sulfide and typical oxidants.


Molar mass g/mol 59.09
Melting point °C -110

Methods for preparation of thiocyanic acid:

2KNCS(solid) + H2SO4(conc.) = 2HNCS↑ + K2SO4 (на coldоду, vacuum).

KNCS(damp) + KHSO4(solid) = time = HNCS + K2SO4 (normal temp., vacuum).

NH4NCS + H3O(+)(cation exchanger) = HNCS + NH(+)4 (cation exchanger) + H2O.


Chemical reactions with thiocyanic acid:

HNCS(diluted) + H2O = H3O(+) + NCS(-).

3HNCS(conc.) = HCN + H2C2N2S3.

HNCS + 2H2O + HCl(diluted) = CO2↑ + H2S↑ + NH4Cl (boiling).

2HNCS + 2H2O + H2SO4(diluted) = (NH4)2SO4 + 2CSO (40-50° C).

HNCS(diluted) + NaOH(diluted) = NaNCS + H2O.

HNCS + H2O + H2S(gas) = CS2 + NH3 • H2O (normal temp.).

HNCS + 3H2O2(conc.) = HCN + H2SO4 + 2H2O (normal temp.),

5HNCS + 4H2SO4(diluted) + 6KMnO4 = 5HCN + 6MnSO4 + 3K2SO4 + 4H2O.


 

Did you know?

Our tooth enamel is also the most mineralized chemical in our body, and is made up of hydroxyapatite.