Bismuth

Chemical reactions

Reaction of bismuth with acids


Bismuth dissolves in concentrated sulphuric acid, H2SO4 forming SO2, and nitric acid, HNO3, and hydrochloric acid, HCl. With hydrochloric acid in the presence of oxygen, bismuth(III) chloride is produced.

4 Bi(s) + 3 O2(g) + 12 HCl(aq) 4 BiCl3(aq) + 6 H2O(l)


Reaction of bismuth with air


When heated bismuth reacts with oxygen in the air forming bismuth(III) oxide, Bi2O3. The flame is bluish white.

4 Bi(s) + 3 O2(g) 2 Bi2O3(s)


Reaction of bismuth with bases


Bismuth(III) is precipitated by strong alkali as the hydroxide

Bi3+(aq) + 3 OH−(aq) BiOH3(s)


Reaction of bismuth with halogens


Bismuth reacts with fluorine, F2, to form the pentafluoride bismuth(V) fluoride.

2 Bi(s) + 5 F2(g) 2 BiF5(s) [white]

Under controlled conditions, bismuth reacts with the halogens fluorine, F2, chlorine, Cl2, bromine, Br2, and iodine, I2, forming the respective bismuth(III) trihalides.

2 Bi(s) + 3 F2(g) 2 BiF3(s) [gray]
2 Bi(s) + 3 Cl2(g) 2 BiCl3(s) [yellow]
2 Bi(s) + 3 Br2(g) 2 BiBr3(s) [yellow]
2 Bi(s) + 3 I2(g) 2 BiI3(s) [red to gray]

Bismuth(III) is precipitated by iodide. Excess iodide will dissolve the precipitate. The soluble iodide is unstable and hydrolyzed to bismuth oxoiodide

Bi3+(aq) + 3 I−(aq) BiI3(s) [black]
BiI3(s) + (n−3) I−(aq) [BiIn]3−n(s), n= 4, 5, 6
BiI3(s) + H2O(l) BiOI(s) [orange]


Reaction of bismuth with metals/metal ions


Bismuth(III) can be reduced by Sn(II) under alkaline conditions

2 Bi(OH)3(s) + 3 [Sn(OH)3]−(aq) + 3 OH−(aq) 2 Bi(s) + 3 [Sn(OH)6]2−(aq)


Reaction of bismuth with sulfides


Bismuth(III) is precipitated by hydrogen sulfide at ≥ 0.4 M hydrochloric acid. The precipitate is dissolved in hot dilute nitric acid or concentrated hydrochloric acid

2 Bi3+(aq) + 3 H2S(aq) Bi2S3(s) + 6 H+(aq)
Bi2S3(s) + 8 H+(aq) + 2 NO3−(aq) 2 Bi3+(aq) + 3 S(s) + 2 NO(g) + 4 H2O(l)


Reaction of bismuth with water


At red hot, bismuth reacts with water to form the trioxide bismuth(III) oxide, Bi2O3.

2 Bi(s) + 3 H2O(g) Bi2O3(s) + 3 H2(g)

Dilution of an acidic solution of bismuth(III) nitrate with water will give a precipitation of an oxo salt.

6 Bi3+(aq) + 8 H2O(g) + 6 NO3−(aq) [Bi6O4(OH)4](NO3)6(s) [white] + 12 H+(aq)


Quantitative analysis


Method EPA 3050 preparation and EPA-6000 Series Inductively Coupled Plasma Method. A portion of the sample is digested in a combination of acids. The digest is aspirated into an 8,000 K argon plasma where resulting light emission is quantified for 30 elements simultaneously.

Method limit of detection in water = 0.04 mg/L
Method limit of detection in soil = 3.00 mg/kg