fact that liquid hydrofluoric acid is not
an electrolyte?

2. Why does sulphuric acid liberate hydrofluoric acid from its salts?

3. In the preparation of chlorine, what advantages are there in treating
manganese dioxide with a mixture of sodium chloride and sulphuric acid
rather than with hydrochloric acid?

4. Why must chlorine water be kept in the dark?

5. What is the derivation of the word nascent?

6. What substances studied are used as bleaching agents? To what is the
bleaching action due in each case?

7. What substances studied are used as disinfecting agents?

8. What is meant by the statement that hydrochloric acid is one of the
strongest acids?

9. What is the meaning of the phrase _aqua regia_?

10. Cl_{2}O is the anhydride of what acid?

11. A solution of hydriodic acid on standing turns brown. How is this
accounted for?

12. How can bromine vapor and nitrogen peroxide be distinguished from
each other?

13. Write the equations for the reaction taking place when hydriodic
acid is prepared from iodine, phosphorus, and water.

14. From their behavior toward sulphuric acid, to what class of agents
do hydrobromic and hydriodic acids belong?

15. Give the derivation of the names of the elements of the chlorine
family.

16. Write the names and formulas for the binary acids of the group in
the order of the stability of the acids.

17. What is formed when a metal dissolves in each of the following?
nitric acid; dilute sulphuric acid; concentrated sulphuric acid;
hydrochloric acid; aqua regia.

18. How could you distinguish between a chloride, a bromide, and an
iodide?

19. What weight of sodium chloride is necessary to prepare sufficient
hydrochloric acid to saturate 1 l. of water under standard conditions?

20. On decomposition 100 l. of hydrochloric acid would yield how many
liters of hydrogen and chlorine respectively, the gases being measured
under the same conditions? Are your results in accord with the
experimental facts?

CHAPTER XVII

CARBON AND SOME OF ITS SIMPLER COMPOUNDS

~The family.~ Carbon stands at the head of a family of elements in the
fourth group in the periodic table. The resemblances between the
elements of this family, while quite marked, are not so striking as in
the case of the elements of the chlorine family. With the exception of
carbon, these elements are comparatively rare, and need not be taken up
in detail in this chapter. Titanium will be referr