Please show all steps 8 HPo K75 x 10 K42 103 Ku62 10 a You

Please show all steps

-8 H,Po, K-75 x 10 K,,-4.2 × 10-3 Ku=6.2 × 10 a. You need to make 9o0. mL of a buffer that has a pH of 7.50 in which the least concentrated buffer component has a concentration of o.20 M. How would you make this buffer if the available compounds are K,HPO46), 3.00 M HCl (), and 3.oo M NaOH (ag)?

a. To prepare a buffer HPO4^2-/H2PO4- (base/acid) components

pH of buffer = 7.50

pKa = 7.20

buffer concentration = 0.20 M x 0.900 L = 0.18 mol

0.18 mol = (H2PO4-) + (HPO4^2-) ---- (1)

Using Hendersen-Hasselbalck equation,

pH = pKa + log(base/acid)

7.50 = 7.20 + log(HPO4^2-/H2PO4-)

(HPO4^2-) = 2(H2PO4-)

feed in (1),

(H2PO4-) + 2(H2PO4-) = 0.18 mol

(H2PO4-) = 0.18 mol/3 = 0.06 mol

Volume 3.0 M HCl needed to add = 0.06 mol x 1000/3 M = 20 ml

(HPO4^2-) = 0.18 - 0.06 = 0.12 mol

mass K2HPO4 needed = 0.12 mol x 174.2 g/mol = 20.904 g

b. To prepare a buffer HPO4^2-/H2PO4- (base/acid) components