54 



SMITH'S INTERMEDIATE CHEMISTRY 



order in which the metals stand in the adjoining list. The most 

 active metals are at the top. All above hydrogen displace this 

 element from dilute acids (and, with more difficulty, from water) ; 

 those below it do not. 



The first displaces the hydrogen from water so violently that 

 the gas catches fire, the second displaces it vigorously, the third 

 less vigorously. Magnesium requires hot water and 

 iron superheated steam. Copper and the metals 

 following it do not liberate hydrogen from water. 



Again, the upper metals act too violently on dilute 

 acids, and zinc is used to prepare the gas. Copper 

 and the metals following it do not displace hydrogen 

 from dilute acids. 



Still again, we recall the fact (p. 36) that, when we 

 heat metals in pure oxygen, the last three do not be- 

 come oxidized at all. Those preceding silver do com- 

 bine with pure oxygen mercury with difficulty, and 

 the others more and more vigorously as we ascend 

 the list. On the other hand, if we start with the 

 oxides of all the metals, we find that those at the 

 foot of the list, up to and including mercuric oxide, 

 lose all their oxygen when heated, 

 leaving the metal. 



Other facts of a similar nature will 

 be mentioned as we encounter them. 

 Meantime, it may be noted that the metals found 

 uncombined in nature are those following hy- 

 drogen. Again, the metals known to have been 

 first used by the human race were gold and silver. 

 In the "bronze age" means of liberating copper 

 from its ores had been discovered. Lead, tin, and 

 iron came later. The list, read from the bottom 

 up, gives, therefore, roughly, the historical order in which the 

 metals came into use. 



ORDER OP 



ACTIVITY. 

 Metala 



Potassium 

 Sodium 

 Calcium 

 Magnesium 

 Aluminium 

 Manganese 

 Zinc 



Chromium 

 Iron 

 Nickel 

 Lead 

 Tin 



- Hydrogen 

 Copper 

 Bismuth 

 Antimony 

 Mercury 

 Silver 

 Platinum 

 Gold 



FIG. 27 



