Lesson I.j 



CHEMISTRY. 



101 



CHEMISTRY. 



QUESTIONS AND EXPLANATIONS. 



1. T. WHAT is Chemistry ? 



/'. It is that science which enables us 



to discover the nature and properties o 



ments of matter, their action upon 



each other, and their combinations ; the 



proportions in which these elements unite, 



the mode of changing compound bodies 



itnple ones, or single bodies into 



compound; and the laws which govern 



their action. 



What is the term chemistry de- 

 rived i 



/'. It b of doubtful derivation; but is 

 probably derived from the Coptic root, 

 chfms, which means obscure or secret. 



Do you remember the general 

 properties of m.r 



/' Yc> ; extension, impenetrability, 

 mobility, extreme divisibility, gravitation, 

 porosity, and indestructibility. 

 [The pupil should be requested to define these 

 terms, and, if not able to do so, should con- 

 sult Cat. I.] 



What are the secondary proper- 

 ties of matter ? 



P. Opacity, transparency, softness, 

 hardness, elasticity, colour, density, so- 

 lidity, fluidity, and others of a similar 



(These terms should be explained to the student, 

 According to their general acceptation. Thu, 

 co*l is *?*; 9 la* is transparent; clay 

 toft; fcM OTf, ft*] 



5. T. What do the various phenomena 

 of chemistry chiefly depend on? 



1 he modifications of attractive and 

 e force, exercised on particles of 

 matter placed at Insensible distances from 

 each other. 



nn me what are the at: 

 ffttef 



P. 1. ftteifcv at traction, or the attrac- 

 "* if **t r*g*4to*. 2. Chemical attraction 



. 



[SeLeMn VIII., p. Jl.] 



at are the repulsive agents f 



and Galvanism. 



[SeeLewonlX., p. J2.J 



8. T. When we change a compound 

 body into simple ones, what is the process 

 termed ? 



P. Decomposition or analysis, which 

 chemists have divided into simple and com- 

 pound, or single and double decomposition. 

 Thus, when a body composed of two sub- 

 stances is decomposed by means of a third 

 body, which acts simply, it is called single 

 or simple decomposition. If the intervention 

 of the third body causes two new com- 

 pounds instead of one, the operation is 

 then called compound, or double decompo- 

 silion. 



9- T. What is the term analysis derived 

 from? 



P. The Greek word analuo (o'wAt/w), 

 / dissolve, and therefore means the resolu- 

 tion of a substance into its component 

 puts. Analysis was first scientifically 

 pursued by Bergman of Sweden. 



10. T. When two simple bodies are 

 changed into a compound body, what is 

 the process termed .' 



P- Synthesis or composition, which is di- 

 rectly opposed to analysis. 



11. y.What is the term derived from ? 

 /'.Two Greek words, soon (<rw), with, 



and tithemi (TI^TJ/LU), I place. 



1- ' <'. :i.e examples of analysis 

 and synthesis. 



/' If I decompose water by galvanism, 

 and cause the evolution of oxygen and hy- 

 drogen gases at the opposite" poles, I ex- 

 it analytically; but if I explode 

 .hese two gases and cause them to i 

 bine so as to form the water, which had 

 jreviously 1,,-,-n decomposed, I examine 



helically. 



13. T. You hare made use of the terms 

 limplc and compound bodies several times, 

 explain their meaning. 



v simple body, or element, is n sub- 

 stance that ciniiiit In- fun!; 

 or resolved into any other kind of mat 



ijas oxygen. A compound 

 body is compose,. 'stances, 



r nature ai 

 /< of sodium or c 



