shirabe.org
Meaning
  1. 1
    English · JMdict
    chemistry disulfuric acid
  2. 2
    English · Wikipedia

    Disulfuric acid (alternative spelling disulphuric acid) or pyrosulfuric acid (alternative spelling pyrosulphuric acid), also named oleum is an oxyacid of sulfur. It is a major constituent of fuming sulfuric acid, oleum and this is how most chemists encounter it. It is also a minor constituent of liquid anhydrous sulfuric acid due to the equilibria: H2SO4 ⇌ H2O + SO3SO3 + H2SO4 ⇌ H2S2O7 The acid is prepared by reacting excess SO3 with sulfuric acid: H2SO4 + SO3 → H2S2O7 Disulfuric acid can be seen as the sulfuric acid analogue of an acid anhydride. The mutual electron-withdrawing effects of each sulfuric acid unit on its neighbour causes a marked increase in acidity. Disulfuric acid is strong enough to protonate "normal" sulfuric acid in the (anhydrous) sulfuric acid solvent system. There are salts of disulfuric acid, commonly called pyrosulfates, e.g. potassium pyrosulfate. There are other related acids with the general formula H2O·(SO3)x though none are isolable.

    Read full article on Wikipedia · CC-BY-SA

Save this word to start reviewing it with spaced repetition. Save word

Grammar codex

What the coloured tags mean

Hiragana

ひらがな

The rounded, flowing kana. Hiragana writes native Japanese words, grammar endings, and anything without (or alongside) kanji — it's the first script you learn. Each character stands for one syllable.

Example

ねこ — cat