Question

A solution with a hydrogen ion concentration [H+] of 1.0 x 10-4 M is more acidic than a solution with a [H+] of 1.0 x 10-9 M.

True
False

Answer 1

Answer:

True.

Explanation:

• As the concentration of [H⁺] of (1.0 x 10⁻⁴ M) is higher than that of (1.0 x 10⁻⁹ M), so the solution with [H⁺] of (1.0 x 10⁻⁴ M) is highly acidic.

• From the calculation point of view:

We can calculate the pH of the solution using the relation: pH = - log[H⁺].

pH is a logarithmic scale used to specify the acidity or basicity of an aqueous solution.

pH (0-7) is the acidic region and (7-14) is the basic region.

As the value of pH is lower means highly acidic solutions.

• The pH of [H⁺] of (1.0 x 10⁻⁴):

pH = - log[H⁺] = - log(1.0 x 10⁻⁴) = 4.0.

• The pH of [H⁺] of (1.0 x 10⁻⁹):

If we calculate pH directly, we will found that the pH of this acid is 9 and this is not accepted.

Actually, it is very diluted acid that has a pH of 7.0 because there is another source of [H⁺] from water that has a concentration of (1.0 x 10⁻⁷).

So, the concentration of [H⁺] is (1.01 x 10⁻⁷).

∴ pH = - log[H⁺] = - log(1.01 x 10⁻⁷) = 6.995.

It is clear that A solution with a hydrogen ion concentration [H+] of 1.0 x 10⁻⁴ M is more acidic than a solution with a [H+] of 1.0 x 10⁻⁹ M.

So, this statement is true.