Question

a buffer is prepared by adding 1.00 l of 1.0 m hcl to 750 ml of 1.5 m nahcoo. what is the ph of this buffer? [ka (hcooh)

Answer 1

Answer:The pH of a buffer prepared by adding 1.00 L of 1.0 M HCl to 750 ml of 1.5 M NaHCOO is 2.84

What is pH?

pH is a measure of the acidity of a solution.

pH is calculated from the negative logarithm to base ten of the hydrogen ions concentration of the solution.

For weak acids such as those used in the preparation of buffers, the acid dissociation constant, Ka are used to determine the pH of the solution.

Therefore, from the Ka of acetic acid, the pH of a buffer prepared by adding 1.00 L of 1.0 M HCl to 750 ml of 1.5 M NaHCOO is 2.84

Answer 2

To find the pH of a buffer solution, use the Henderson-Hasselbalch equation and calculate the concentrations of [A¯] and [HA].

In order to find the pH of a buffer solution, we need to use the Henderson-Hasselbalch equation:

pH = pKa + log([A¯]/[HA])

Given that the Ka for HCOOH is 1.8 x 10^-5, we can calculate the pKa as -log(Ka) = -log(1.8 x 10^-5).

Next, we need to calculate the concentrations of [A¯] and [HA] in the buffer solution. We know that 1.00 L of 1.0 M HCl and 750 mL of 1.5 M NaHCOO are added to prepare the buffer. Using the balanced equation for the dissociation of NaHCOO, we can calculate the moles of NaHCOO and the resulting concentrations of [A¯] and [HA]. Finally, substitute these values into the Henderson-Hasselbalch equation to find the pH of the buffer solution.