Flame Color Test for Tin

Abstract

Meissner's flame color test for tin has been investigated. The test is carried out as follows: The sample is mixed with concentrated hydrochloric acid and zinc, a test tube filled with water is dipped in this solution and the tube is held over the flame of a Bunsen burner to give a characteristic blue flame.
The addition of zinc is found unnecessary in this case but the presence of hydrochloric acid is essential for this flame color reaction. The Sn⁴⁺ (0.010.05%) is distilled with hydrochloric acid vapor by heating the hydrochloric acid solution at about 150°C and the vapor gives a characteristic blue color in the Bunsen flame. Although Sn²⁺ is not distilled with hydrochloric acid, it gives colored flame by heating the hydrochloric acid solution in the Bunsen flame as it is rapidly oxidized to Sn⁴⁺.
The above results confirmed that the flame color reaction for tin depends chiefly upon the volatility of SnCl₄ (bp 114°C) and the reduction to SnH₄ as reported by Meissner is unnecessary.