H n.
some words, mostly derived or introduced from foreign languages, h following c and g indicates that those consonants have the hard sound before e, i, and y, as in chemistry, chiromancy, chyle, Ghent, Ghibelline, etc.; in some others, ch has the sound of sh, as in chicane. See Guide to Pronunciation, §§ 153, 179, 181-3…
HYDROFLUORIC a.
ric acid on fluorite, and is usually collected as a solution in water. It attacks all silicates, as glass or porcelain, is the agent employed in etching glass, and is preserved only in vessels of platinum, lead, caoutchouc, or gutta-percha.
INDICATOR n.
That which indicates the condition of acidity, alkalinity, or the deficiency, excess, or sufficiency of a standard reagent, by causing an appearance, disappearance, or change of color, as in titration or volumetric analysis.