112 



CHEMISTRY. 



[lesson VII. 



Names of Metals continued. 



Jfame. 



Magnesium 



Manganese 



Mercury (Hydrangyrum) 



Molybdenum 



Nickel 



Kiobium 



Osmium 



Palladium 



Pelopium 



Platinum 



Potassium (Kalium) 



Rhodium 



Ruthenium 



Selenium 



Silicium 



Silver (Argentum) 



Sodium (Natronium) 



Strontium 



Tanivlium 



Terbium 



Tellurium 



Thorium 



Tin (Stannum) 



Titanium 



Tungsten (tt'olframium) 



Uranium 



Vanadium 



Yttrium 



Zinc 



Ziuconium 



Symbol. 



Mg. 



Mn. 



Hg. 



Mo. 



Ni. 



? 



Os. 



Pd. 



r 

 Pt. 



K. 



R. 



Ru. 



Se. 



Si. 



Ag. 



Na. 



Sr. 



Ta. 



T 



Te. 



Th. 



St. 



Ti. ' 



W. ' 



U. 



V. 



Y. 



Zn. 



Zr. 



Equiv. 



127 



27-fi 

 101-4 



43 



29-6 



? 



99-6 



53-4 



? 



987 



39-2 



52-1 



51 7 



40 



14-8 

 108M 



23-2 



44 

 185 



r 



fi4 

 596 

 59 

 2^-5 

 95 

 217 

 68-6 

 32-2 

 322 

 22-4 



C9. T. Will these equivalents enable 

 us to find the composition of the compounds 

 of these elements ? 



P. Yes. We can learn that by finding 

 out the weight of the atoms of its in- 

 gredients, from the groups we have ex- 

 amined, and adding them together : thus, 

 Oxide of Copper is expressed by Cu O ; 

 and, as we know that the equivalent of 

 copper is 3T8, and that of oxygen 8, we 

 add them together, and that gives us the 



atomic weight of oxide of copper viz 

 3<)-S. 



70. T. Can we find the composition of 

 any compound as easily ? 



P. Yes. For example, Peroxide of 

 Manganese is represented by Mn O 2 , and 

 by adding 27'6, the equivalent of man- 

 ganese, to 16, which is equal to two atoms 

 of oxygen, we get 43'6 as the product, 

 which is the atomic weight. Let us take 

 sulphuret of bismuth for another example ; 

 the symbol for this is Hi 2 and S 3 , and, by 

 the same rule, we find that its equivalent 

 is 260 8. 



[The pupil should be requested to explain the 

 meaning of the following symbols, and to give 

 their equivalents viz., Cu2 S; Pb S ; Cd S ; 

 H S5; AsFe3; Zu O, S O3, 7 HO.] 



71. T. Have not some chemists pro- 

 posed the adoption of other terms, instead 

 of sulphuret and phosphuret ? 



P. Yes, Professors Graham and Hoff- 

 mann propose using the terms sulphide and 



GENERAL QUESTIONS ON LESSON VI. 



1. Explain the meaning of the various 

 prefixes to chemical names. 



2. When the names of acids end in ic, 

 how do the names of their salts terminate ? 



3. When acids end in ous, how do the 

 names of their salts terminate ? 



4. How do the names of most metals and 

 alkalis end ? 



5. Give the symbols and equivalents of 

 each group of elementary bodies. 



6. How can we find the equivalents of 

 compound bodies ? 



LESSON VII. 



WE have already noticed some of the peculiarities and properties of heat (p. 22), 

 but as some of the processes in connexion with the science of chemistry are under 

 great obligations to this agent, we must notice some other properties belonging to it. 

 Heat or Caloric is the great agent of repulsion, as its particles repel each other. 

 It causes bodies to expand, and pass from a solid to a liquid, and from a liquid to 

 a gaseous form, and we are enabled to observe the changes of temperature by availing 

 ourselves of this property. Thus we measure the degrees of heat by means of a 

 thermometer (Fig. 13), an instrument constructed for materials which readily expand 



