nitrogen.
Penta-nitro-cellulose C_{24}H_{35}O_{20}(NO_{2})_{5} = 8.04 per cent.
nitrogen.
Tetra-nitro-cellulose C_{24}H_{36}O_{20}(NO_{2})_{4} = 6.77 per cent.
nitrogen. (= old mono-nitro-cellulose)

It is not unlikely that a long series of nitrates exists. It is at any
rate certain that whatever strength of acids may be used, and whatever
temperature or other conditions may be present during the nitration, that
the product formed always consists of a mixture of the soluble and
insoluble nitro-cellulose.

Theoretically 100 parts of cotton by weight should produce 218.4 parts of
gun-cotton, but in practice the yield is a good deal less, both in the
case of gun-cotton or collodion-cotton. In speaking of soluble and
insoluble nitro-cellulose, it is their behaviour, when treated with a
solution consisting of 2 parts ether and 1 of alcohol, that is referred
to. There is, however, another very important difference, and that is
their different solubility in nitro-glycerine. The lower nitrates or
soluble form is soluble in nitro-glycerine under the influence of heat, a
temperature of about 50° C. being required. At lower temperatures the
dissolution is very imperfect indeed; and after the materials have been
left in contact for days, the threads of the cotton can still be
distinguished. The insoluble form or gun-cotton is entirely _insoluble_ in
nitro-glycerine. It can, however, be made to dissolve[A] by the aid of
acetone or acetic ether. Both or rather all the forms of nitro-cellulose
can be dissolved in acetone or acetic ether. They also dissolve in
concentrated sulphuric acid, and the penta-nitrate in nitric acid at about
80° or 90° C.