Table of Contents
1. Ligroin
- Heavy Naphtha
Petroleum fraction consisting mostly of C₇ and C₈ hydrocarbons.
2. Alum
Monovalent metal + Trivalent metal + Sulfate crystal
Potassium aluminum sulface, the alumen, being the most common.
3. Purple Gold
\[ \rm AuAl_2 \]
- Glimmer like gold and purple colored.
In electronic industry, it is called purple plague, because it is a brittle degradation of gold that mixed with aluminum.