A substance that produces hydroxide ions when placed in water is a base. When a base is dissolved in water, the molecule will form into ions and bases produce OH- ions. Meanwhile, acids produce H+ in water.
Answer: A substance that produces hydroxide ions when placed in water is base.
Explanation:
Bases are the substance:
Where as acid gives positively charged hydronium ion([tex]H^+[/tex]) in aqueous solution.