What is the [H+] if the pH of a solution is 7.90

PH scale is used to determine how acidic, basic or neutral a solution is.

pH is calculated using the hydrogen ion concentration

pH = - log[H⁺]

if we know the pH we can calculate the H⁺ concentration

[H⁺] = antilog (-pH)

[H⁺] = 1.26 x 10⁻⁸ M

therefore [H⁺] is 1.26 x 10⁻⁸ M