What is the pH of buffer solution formed by mixing 0.01 M acetic acid and 0.05 M sodium acetate ( pK ₂=4 7447 )

Step-by-step solution

For an acidic buffer solution, the pH is determined using the Henderson-Hasselbalch equation: pH = pK_a + ( [ Salt ] [ Acid ] ) . Given [ Acid ] = 0.01 M , [ Salt ] = 0.05 M , and pK_a = 4.7447 , the ratio is [ Salt ] [ Acid ] = 0.05 0.01 = 5 . Since (5) 0.69897 , the pH is calculated as pH = 4.7447 + 0.69897 = 5.44367 . Rounded to two decimal places, the pH is 5.44 , which corresponds to option C .