Suppose 5 moles of a weak acid (HA) were mixed with 2 moles of a

1
Suppose 5 moles of a weak acid (HA) were mixed
with 2 moles of a strong base (OH-) in a 1.0 L
flask. Given the Ka 1.0 x 10-6, determine the
pH.
CHEMISTRY 1st HA OH- ? H2O
A- xsHA
Initial 5 2
0 ?
Change -2 -2
2
After RXN 3 0
2 3 xsHA
Now for Equilibrium xsHA H2O ?
H3O A-
I. 3 0
2
C. -x x
x
E. 3-x x
2x
try dropping both the x and the x terrms
x 1.5 x10-6 H3O
pH -log H3O 5.82