(Solved): A buffer contains 0.050mol of lactic acid (pKa=3.86) and 0.090mol of sodium lactate per lite ...

A buffer contains $0.050\mathrm{mol}$ of lactic acid $\left(\mathrm{p}{K}_{\mathrm{a}}=3.86\right)$ and $0.090\mathrm{mol}$ of sodium lactate per liter. WThe chemical structure of lactic acid and it's sodium salt sodium lactate. Lactic acid's structural formula is $\mathrm{C}3\mathrm{H}6\mathrm{O}3$ and it contains a carbon bonded to a methyl group, a secondary hydroxyl, and a carboxyl group. Sodium lactate is a salt such that the negative charge of the lactate anion associates with the positively charged sodium ion. Calculate the $\mathrm{pH}$ of the buffer. buffer $\mathrm{pH}$ : Calculate the change in $\mathrm{pH}$ after adding $6.0\mathrm{mL}$ of $0.40\mathrm{M}\mathrm{HCl}$ to $1.0\mathrm{L}$ of the buffer. buffer $\mathrm{pH}$ change: units Calculate the change in $\mathrm{pH}$ after adding $6.0\mathrm{mL}$ of $0.40\mathrm{M}\mathrm{HCl}$ to $1.0\mathrm{L}$ of pure water. water $\mathrm{pH}$ change: