Acid Base Reactions

Answers for Acid-Base Reactions worksheet

Skill Development Exercises

Make sure your significant digits are correct in the following calculations.

7. (1.0 L)(6.0 M HBr) = 6.0 mol HBr
M(HBr) = 1.0079 g mol^-1 + 79.904 g mol^-1 = 80.912 g mol^-1
(6.0 mol HBr)(80.912 g mol^-1 ) = 490 g

8. M(KOH) = 39.098 g mol^-1 + 15.999 g mol^-1 + 1.0079 g mol^-1 = 56.105 g mol^-1
2.500 g / 56.105 g mol^-1 = 0.04456 mol KOH
0.04456 mol / 0.1000 L = 0.4456 M KOH

9. (2.5 M)(5.0x10^-3 L) = 1.3x10^-2 mol H₂SO₄

10. (2.5 M)(5.0x10^-3 L) = 1.3x10^-2 mol H₂SO₄
Molarity = moles / volume = (1.3x10^-2 mol ) / (25.00x10^-3L) = 0.52 M
if you calculate it in one step: (2.5 M)(5.0x10^-3 L) / (25.00x10^-3L) = 0.50 M
different points of rounding affect the last digit

11. (15.00x10^-3 L)(3.0 M) = 4.5x10^-2 mol HNO₃
need 4.5x10^-2 mol NaOH to neutralize
4.5x10^-2 mol / 6.0 mol L^-1 = 7.5x10^-3 L (or 7.5 mL)

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