硫酸 りゅうさんナトリウムでしょう
aryūsannatoriumudeshō

Noun
Desu Copula

Expresses probability in a polite manner ("probably…") of 亜硫酸ナトリウム

1. Sodium bisulfite, probably.; Sodium metabisulfite, probably.

Polite
Presumptive
Conjecture