Quick Review Cards for Medical Laboratory Science

Chemistry Calculationscontinued Clinical Chemistry Review 133

FORMULA EXAMPLE

% concentration = grams or milliliters per 100 mL

N = M × valence

V 1 C 1 = V 2 C 2

What is the concentration in % of a solution that contains 8.5 grams of

NaCl per liter?

8.5 g = x

1,000 mL 100 mL

1,000 x = (8.5) × 100

x = 0.85%

What is the normality of a 3 M H 2 SO 4 solution?

N = 3 × 2 = 6

What is the molarity of a 0.3 N H 2 SO 4 solution?

M = 0.3 = 0.15

2

How many mL of 95% alcohol are needed to prepare 100 mL of 70% alcohol?

(x)(95) = (100)(70)

x= 73.7 mL

V = volume, C = concentration.