EXERCISES
1. How does pyrolusite effect the decolorizing of glass containing iron?
2. Write the equations for the preparation of manganous chloride, carbonate, and hydroxide.
3. Write the equations representing the reactions which take place when ferrous sulphate is oxidized to ferric sulphate by potassium permanganate in the presence of sulphuric acid.
4. In the presence of sulphuric acid, oxalic acid is oxidized by potassium permanganate according to the equation
C2H2O4 + O = 2CO2 + H2O.
Write the complete equation.
5. 10 g. of iron were dissolved in sulphuric acid and oxidized to ferric sulphate by potassium permanganate. What weight of the permanganate was required?
6. What weight of ferrochromium containing 40% chromium must be added to a ton of steel to produce an alloy containing 1% of chromium?
7. Write the equation representing the action of ammonium sulphide upon chromium sulphate.