The ferricoxide of the cement is unaffected by sea- water.
2
The precipitate may then be ignited and weighed as ferricoxide, as described on page 110.
3
These generally consist of ferricoxide and alumina.
4
Agate is stained red, so as to form carnelian and sardonyx, by means of ferricoxide.
5
The iron is oxidized to ferricoxide.]
6
The aluminium is then determined by difference, after subtracting the weight of ferricoxide corresponding to the amount of iron found.
7
It is a common practice to determine the iron, calculate it to ferricoxide, and so to estimate the alumina indirectly.
8
Since a high temperature tends to lessen the solubility of ferricoxide, the heat should not be raised above low redness.]
9
The residue after ignition consists of ferricoxide, alumina, and mangano-manganic oxide (Mn_{3}O_{4}), if manganese is present.
10
From the weight of ferricoxide (Fe_{2}O_{3}) calculate the percentage of iron (Fe) in the sample (Note 3).
11
The ash is made up of silica, 55.6; ferricoxide, 12.2; alumina, 22.14; lime, 1.5; sulphur, 0.9; soluble salts (containing 0.92 per cent.
12
The American bauxites contain from 38 to 67% of alumina, from 1 to 23% of ferricoxide, and from 1 to 32% of silica.
13
A sample of magnesia limestone has the following composition: Silica, 3.00%; ferricoxide and alumina, 0.20%; calcium oxide, 33.10%; magnesium oxide, 20.70%; carbon dioxide, 43.00%.
14
Ferricoxide is the most abundant ore of iron and occurs in great deposits, especially in the Lake Superior region.
15
[Note 2: Ignited ferricoxide is somewhat hygroscopic.