Question

If the same volume of the buffer were 0.270 mm in nh3 and 0.400 mm in nh4br, what mass of hcl could be handled before the ph falls below 9.00? Express the mass in grams to three significant figures.

Answer 1

The student's question involves using the Henderson-Hasselbalch equation to calculate the mass of HCl that a buffer can neutralize before its pH drops below 9.00. We need to find the number of moles of HCl and then convert it to grams to find the mass.

Step-by-step explanation:

The question asks to calculate the mass of HCl that can be handled by a buffer system before the pH falls below 9.00, given the concentrations of NH3 and NH4Br in the buffer. The calculation involves using the Henderson-Hasselbalch equation to determine how much HCl (a strong acid) can be added to the buffer without depleting the buffering capacity. To find the mass of HCl, we first need to calculate the amount of buffer present then identify how many moles of HCl can be added until the pH limit is reached. Once we know the number of moles of HCl, we use its molar mass to convert it to grams.