Which of these substances is an arrhenius acid?

a. c2h6 (g)

b. ch4 (g)

c. hbr (g)

d. koh (s) e. na3po4?

The answer to this question would be: c. HBr (g)

Arrhenius concept of acid is the molecule that will form hydrogen ion when dissolved in aqueous solution. Hydrogen bromide of HBr will form a hydrogen ion and a bromide ion.

Kalium hydroxide or KOH will release OH - ion so it would be a base.