An Introduction to Chemical Science

ibility

it 5 cc. of water, shake well, boil for a minute, holding the t.t. obliquely in the flame, using for the purpose a pair of wooden nippers (Fig. 3). If the sugar does not disappear, add more water. When cool, touch a

ig

ts in a receiver (Fig. 5). After filtering, notice whether any residue is left on the filter paper. Taste a drop of the filtrate. Has sugar gone through the filter? If so, what do you infer

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ill the sweet taste would have remained. Thus the small quantity of sugar

de. A solution of.00000002 g. of the red coloring matte

uss here lead to the belief that such a limit does exist; that there are particles of sugar, and of all substances, which are incapab

tance larger than a molecule; i

st particle of a substan

y divided state than otherwise, but it is not

o still smaller particles of something else? May it not be a compound body, and will not som

, and add slowly 4 cc.of strong sulphuric acid. Note any chan

t have either added something to the sugar molecules, or subtracted something from them. It was the latter. Here, then, is a force entirely different from the one which tends to reduce masses to molecules. The molecule has the same properties as the

osed of letters which alone do not resemble the word. But can the charcoal itself be resolved into other substances, and these into still others, and so on? Carbon is one of the substances from which noth

ivisible substance, or one from w

of elements united in exact proportions by

ements or compounds blended together, b

s does sugar belong? Carbon? T

; we call its smalle

er into combination. Atoms are indivisible and usually do n

that of a compound may have two, or it may have hundr

arbon? A molecule? Did the chemical affinity of the acid break up masses or molecules? In this respect it is a type of all chemical action. The distinction between physics and chemistry is here well shown. The molecule is the unit of the physicist, the atom that of the chemist. However large the masses changed by chemical action, that

ration of compounds

lding up of compound

thesis is an exchange of atoms in two different c

ly different properties. Sulphur and carbon are two stable solids. The chemical union of the two forms a volatile liquid. A substance may be at one ti

of heat, souring of milk, evaporation of water, decay of vegetation, burning of wood,

implest forms, and of the various c