Engineering Board Exam Reviewer · Chemistry · medium

What is the molarity of a solution prepared by dissolving 20 g of NaOH in enough water to make 500 mL of solution? (Use H = 1, C = 12, N = 14, O = 16, Na = 23, S = 32, Cl = 35.5, Ca = 40)

  1. 0.5 M
  2. 40.0 M
  3. 1.0 M
  4. 0.25 M

Answer

C. 1.0 M

Solution

n = 20/40 = 0.5 mol. M = 0.5/0.5 L = 1.0 M.

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