A 0.21-mol sample of a diprotic acid, H 2A, is dissolved in 250 mL of water. The K a1 of this acid is 1.0 × 10 –5 and K a2 is 1.0 × 10 –10. Calculate the concentration of A 2– in this solution. a.
0.84 M
b.
1.0 × 10–5 M
c.
1.4 × 10–3 M
d.
1.0 × 10–10 M
e.
2.9 × 10–3 M