The only wrong step I see is the 2:1 mole ratio. You\'resupposed to multiply by 2. .0525 moles Ba(OH)2 * 2 moles HCL/ 1mol Ba(OH)2 = 0.105 mols Ba(OH)2 You should have only 1 sig fig because you go with the least numberwhich is 1. Solution The only wrong step I see is the 2:1 mole ratio. You\'resupposed to multiply by 2. .0525 moles Ba(OH)2 * 2 moles HCL/ 1mol Ba(OH)2 = 0.105 mols Ba(OH)2 You should have only 1 sig fig because you go with the least numberwhich is 1..