過か臭しゅう素そ酸さん

Meanings

1

perbromic acid

Technical term in chemistry; refers to the inorganic compound with formula HBrO₄.

臭しゅう素そ酸さん
Bromic acid (HBrO₃); perbromic acid has one more oxygen atom and is a stronger oxidizer.
次じ亜あ臭しゅう素そ酸さん
Hypobromous acid (HBrO); a weaker bromine oxoacid with fewer oxygen atoms.

Compound of 過 (per-) + 臭素 (bromine) + 酸 (acid), following standard Japanese chemical nomenclature.