Answer is: tomatoes is thousand (1000) times more acidic than water. pH(tomato) = 4.00. pH(water) = 7.00. pH = -log[H⁺<span>]. </span>[H⁺] = 10∧(-pH); concentration of hydrogen ions. [H⁺] = 10⁻⁴ M = 0.0001 M; tomato. [H⁺] = 10⁻⁷ M = 0.0000001 M; water. [H⁺](tomato) /[H⁺](water) = 0.0001 M ÷ 0.0000001 M. [H⁺](tomato) /[H⁺](water) = 1000.