Multiple choice Which of the following is a dibasic acid? Nitir acid Sulphuric acid Phosphoric acid Sodium carbonate Reveal answer Fill a bubble to check yourself B Correct answer Explanation A dibasic acid has two acidic hydrogen atoms in its molecules which can be ionised. Sulphuric Acid, H2SO4, is a dibasic acid, because it contains two hydrogens atoms which ionise in aqueous solution to become Hydrogen Ions, H+.