By the intervention of sulphuric acid, which combines with the potash, and sets the nitric acid at liberty. This I can easily show you, by mixing some nitrat of potash and sulphuric acid in this retort, and heating it over a lamp; the nitric acid will come over in the form of vapour, which we shall collect in a glass bell. This acid, diluted in water, is commonly called aqua fortis, if Caroline will allow me to mention that name.
CAROLINE.
I have often heard that aqua fortis will dissolve almost all metals; it is no doubt because it yields its oxygen so easily.
MRS. B.
Yes; and from this powerful solvent property, it derived the name of aqua fortis, or strong water. Do you not recollect that we oxydated, and afterwards dissolved, some copper in this acid?
EMILY.
If I remember right, the nitrat of copper was the first instance you gave us of a compound salt.
CAROLINE.
Can the nitric acid be completely decomposed and converted into nitrogen and oxygen?
EMILY.