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關於Detection of substances的化學問題
1. A student collected samples of two minerals – X and Y. Both minerals are colourless and crystalline, though Y is obviously mixed with small amounts of a reddish brown solid. X is insoluble in water while Y is almost completely soluble. The following table shows the results of tests conducted on X and Y.
X gave a dull red flame colour.
Y gave a yellow flame colour.
X was added to dilute hydrochloric acid
X dissolved in dilute hydrochloric acid with the evolution of a gas that turned limewater milky.
Dilute nitric acid was added to a solution of Y, followed by silver nitrate solution
A white precipitate formed.
a) The reddish brown solid mixed with Y is insoluble in water. Suggest how you would show that it contains iron(III) ion.
- 1 十年前最愛解答
Reacting the solid with sodium hydroxide solution. Fe3+ gives reddish brown precipitate.
Fe3+ (aq) + OH- (aq) -> Fe(OH)3 (s) <- reddish brown!!
Hope my explanation help.資料來源： myself.
- ShingMingTonyLv 71 十年前
Test the reddish brown solid with sodium hydroxide solution. If reddish brown percipitaten is form, it contain iron(III) ion