1. All of the water in a 0.200 M solution of K2CO3 was evaporated and 0.15 mols of K2CO3 was obtained. what was the original volume of the sample?
2. What is the pH of a 16 mM solution of Calcium Hydroxide?
2. What is the pH of a 16 mM solution of Calcium Hydroxide?
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1. All of the water in a 0.200 M solution of K2CO3 was evaporated and 0.15 mols of K2CO3 was obtained. what was the original volume of the sample?
M1V1 = M2V2
M1 = 0.200 M
V1 = 1 L
M2 = 0.15 M
V2 = unknown
V2 = M2/(M1V1) = (0.15)/((0.200)*(1)) = 0.75 L (or 750 mL)
2. What is the pH of a 16 mM solution of Calcium Hydroxide?
Ca(OH)2 → Ca^2+ + 2OH-
16 mM Ca(OH)2 → 16 mM Ca^2+ + 32 mM OH-
pOH = -log[OH-] = - log(0.032 mol/L) = 1.49
pH + pOH = 14
pH = 14 - pOH = 14 - 1.49 = 12.5 (to three sig figs)
1. All of the water in a 0.200 M solution of K2CO3 was evaporated and 0.15 mols of K2CO3 was obtained. what was the original volume of the sample?
M1V1 = M2V2
M1 = 0.200 M
V1 = 1 L
M2 = 0.15 M
V2 = unknown
V2 = M2/(M1V1) = (0.15)/((0.200)*(1)) = 0.75 L (or 750 mL)
2. What is the pH of a 16 mM solution of Calcium Hydroxide?
Ca(OH)2 → Ca^2+ + 2OH-
16 mM Ca(OH)2 → 16 mM Ca^2+ + 32 mM OH-
pOH = -log[OH-] = - log(0.032 mol/L) = 1.49
pH + pOH = 14
pH = 14 - pOH = 14 - 1.49 = 12.5 (to three sig figs)