216 ELEMENTARY GENERAL SCIENCE CH. xiv 



quantity of each in the mixture ? Could you separate sugar from 

 salt in the same way ? 



5. What do you mean by a saturated solution ? How would you 

 prepare a saturated solution at a given temperature ? What is 

 generally the effect of cooling a saturated solution ? 



6. A white powder is shaken up with water. How would you 

 ascertain whether any of it dissolves ? 



7. What is meant by the statement that two liquids mix ? Give 

 examples. Can a liquid be soluble in another liquid without being 

 capable of mixing ? If so, give an example. 



8. How may fresh water suitable for drinking be obtained from 

 sea water ? 



9. By what means would you endeavour to find the quantity of a 

 given solid which a given quantity, say 1 gallon, of water is capable 

 of dissolving? 



10. What is meant by ' ' precipitation ? " Under what circumstance 

 may precipitates be formed in a liquid ? 



11. How would you -endeavour to obtain large crystals of alum ? 



12. Describe an experiment to show the solubility of ether in 

 water. 



13. Sand and salt are stirred up in a bottle containing water in 

 which some gas is dissolved. What methods would you use to recover 

 the sand, salt, and gas from the water ? 



14. Give examples of the solvent power of water. How could 

 you determine whether a sample of water contained dissolved solid 

 matter ? 



15. Describe the apparatus you would employ to obtain water 

 free from dissolved substances. 



16. State in general terms the differences observable between a 

 mixture and a compound of any two substances. 



17. Explain the terms Mixture and Compound. How could you 

 show that copper and sulphur (or iron and sulphur) can exist to- 

 gether, either as a mixture or as a chemical compound ? 



