A 440 mL sample of a 0.100 M formate buffer, pH 3.75, is treated with 4 mL of 1.00 M KOH. What is the pH following this addition? (pK₂ for formic acid is 3.75) Express your answer to two decimal places.

= く O Acids and Bases Calculating the composition of a buffer of a given pH 0/5 a A chemistry graduate student is given 300. mL of a 0.70 M hydrocyanic acid (HCN) solution. Hydrocyanic acid is a weak acid with K = 4.9 x 10 10. What mass of NaCN should the student dissolve in the HCN solution to turn it into a buffer with pH = 9.48? You may assume that the volume of the solution doesn't change when the NaCN is dissolved in it. Be sure your answer has a unit symbol, and round it to 2 significant digits. x10 ㅁ

A buffer contains 0.035 mol of boric acid (pKa = 9.15) and 0.015 mol of sodium borate per liter. (a) Calculate the pH of the buffer.(b) Calculate the pH when 2.5 mL of 0.50 M HCl is added to 0.5 L of the buffer.(c) Calculate the pH when 2.5 mL of 0.50 M HCl is added to 0.5 L of pure water.

You have 0.600 L of an 0.300 M acetate buffer solution (i.e. [HC;H,O2] + [C,H¿O¿¯] = 0.300 M) at pH 5.30. What will the new pH of the solution be if you add 82.0 mL of 1.000 M HCI to it. Acetic acid has a pKa of 4.74.