Question

If it requires 37.5 mL of a 0.245 M HBr solution to neutralize 18.0 mL Mg(OH)2, what is the concentration of the Mg(OH) 2 solution?

2 HBr + Mg(OH) 2 Mg(Br) 2 + 2 H2O

0.0120 M
0.510 M
0.118 M
0.0255 M
@nechirwan

Answer 1

2 HBr + Mg(OH)2 → MgBr2 + 2 H2O

(37.5 mL) x (0.245 M HBr) x (1 mol Mg(OH)2 / 2 mol HBr) / (18.0 mL Mg(OH)2) = 0.0255 M Mg(OH)2

Answer 2

0.0255 M