FOOTNOTES:

[50] "Modern American Methods of Copper Smelting" (Dr. Peters).

[51] "Journal of the Society of Chemical Industry," vol. v. No. 2.

[52] Lead when present is precipitated on the spiral in the form of a dark powder of dioxide (PbO₂). Manganese is also thrown down on the spiral as dioxide (MnO₂), the solution at the same time becomes violet from the formation of permanganic acid.

[53] See the method given under Examination of Commercial Copper.

[54] CuSO₄ + 4KCy = 2KCy.CuCy₂ + K₂SO₄.

[55] 2CuSO₄ + 3KCy + Am₂O = Cu₂Cy₂ + Am₂SO₄ + K₂SO₄ + KCyO.

[56] 2CuSO₄ + 4KI = Cn₂I₂ + 2I + 2K₂SO₄.

[57] 2Na₂S₂O₃ + 2I = 2NaI + Na₂S₄O₆.

[58] For further information, see Appendix B., and a paper by J.W. Westmoreland, Journal of the Society of Chemical Industry, vol. v. p. 48.

[59]
3Cu₂O + 6AgNO₃ + 3H₂O
= 2Cu₂H₃O₃NO₃ + 2Cu(NO₃)₂ + 6Ag.
(Insoluble basic salt.)

[60] K₂CrO₄ + Pb(NO₃)₂ = PbCrO₄ + 2KNO₃

[61] Made by dissolving 12 grams of tartaric acid and 4 grams of stannous chloride in water, and adding potash solution till it is alkaline. The solution should remain clear on heating to 60° or 70° C.

[62] It must be remembered that arsenate of bismuth is completely insoluble in this acid.

[63] SbCl₅ + 2KI = I₂ + SbCl₃ + 2KCl.

FOOTNOTES:

CHAPTER XI.