Ethyl

Ethyl, $(C\_2H\_5)\_2$, is a colourless, inflammable gas, obtained by the action of iodide of ethyl, $C\_2H\_5I$, on granulated zinc. It possesses an agreeable odour, is insoluble in water, but soluble in alcohol. It is not, however, on its own account that ethyl is of importance, but because it is the starting-point of an important series of organic compounds known as the ethyl series. In all of these the group $CH\_2-CH\_2$ or $C\_2H\_5$ is present, and acts as if it were an atom of some elementary substance—e.g. potassium. Thus we have

In these we see that the group of atoms, $C\_2H\_5$, always enters into combination as if it were indivisible, and it is usual to call this group ethyl, and to reserve the term diethyl for the compound $(C\_2H\_5)\_2$ described above. Ethyl, $C\_2H\_5$, is only hypothetical, and does not exist in the free state, while diethyl, $(C\_2H\_5)\_2$, is an actual gas. See ALCOHOL, BASE, and ETHER.