Question

What is the [H+] of an HCl solution if the pH is measured to be 6? Select one: a. 1 X 10-7 M b. 1 X 10-6 M c. 6 X 10-6 M d. 8 X 10-1 M

Answer 1

Answer : The correct option is, $1\times 10^{-6}M$

Explanation :  Given,

The value of pH of HCl = 6

As we know that,

pH : It is defined as the negative logarithm of hydrogen ion or hydronium ion concentration.

The formula of pH is :

$pH=-\log [H^+]$

Now put all the given values in this formula, we get the concentration of hydrogen ion.

$6=-\log [H^+]$

$[H^+]=1\times 10^{-6}M$

Therefore, the concentration of hydrogen ion is, $1\times 10^{-6}M$

Answer 2

$pH=-\log_{10} [H^+] \Rightarrow [H^+]=10^{-pH} \\ \\ pH=6 \\ \ [H^+]=10^{-6}=1 \times 10^{-6}$

The answer is B. 1 × 10⁻⁶ M.