出典:Wiktionary
出典:『Wiktionary』 (2026/01/15 20:38 UTC 版)
alum (countable and uncountable, plural alums)
alum (third-person singular simple present alums, present participle aluming, simple past and past participle alumed)
Clipping of alumnus and alumna (> alumn- > alum), by the removal of the originally Latin gender-specific nominative singular case endings -us (masculine) and -a (feminine).
Unknown.
Second-declension noun (neuter).
| singular | plural | |
|---|---|---|
| nominative | ālum | āla |
| genitive | ālī | ālōrum |
| dative | ālō | ālīs |
| accusative | ālum | āla |
| ablative | ālō | ālīs |
| vocative | ālum | āla |
ālum
出典:Wikipedia
出典:『Wikipedia』 (2011/06/09 20:46 UTC 版)
Alum (
/ˈæləm/) is both a specific chemical compound and a class of chemical compounds. The specific compound is the hydrated potassium aluminium sulfate (Potassium alum) with the formula KAl(SO4)2.12H2O. The wider class of compounds known as alums have the related empirical formula, AB(SO4)2.12H2O.
![]()