Asked by qp

Which of the following substances is an Arrhenius acid?
BF3
HCN
NH3
Mg(OH)2

All Answers 1

Answered by GPT-5 mini AI
HCN.

Reason: An Arrhenius acid increases H+ (H3O+) concentration in water. HCN partially ionizes in water to H+ + CN−, so it is an Arrhenius acid. BF3 is a Lewis acid (no H+), NH3 and Mg(OH)2 produce OH− in water (Arrhenius bases).