If a buffer solution is 0.200M in a weak acid (Ka=1.6*10^-5)and 0.480 M in its conjugate base what should the pH be?
To find the pH of a buffer solution, you can use the Henderson-Hasselbalch equation:
pH = pKa + log ( [conjugate base] / [weak acid] )
In this case, the acid is the weak acid and the conjugate base is the base formed by the dissociation of the weak acid. The pKa of the weak acid is given as 1.6 * 10^(-5).
First, let's calculate the ratio of the conjugate base to the weak acid:
[conjugate base] / [weak acid] = 0.480 M / 0.200 M = 2.4
Next, substitute this ratio and the pKa value into the Henderson-Hasselbalch equation:
pH = 1.6 * 10^(-5) + log(2.4)
To calculate the logarithm, you can use a scientific calculator or mathematical software:
pH ≈ 4.62
Therefore, the pH of the buffer solution should be approximately 4.62.