How many grams of Potassium chromate must be used to make a 3.75 M solution when 1.2 liters of water is used?

Moles of K₂CrO₄ = (3.75 mol/L) × (1.2 L) = 4.5 mol

Molar mass of K₂CrO₄ = 39.1 + 52.0 + 16.0×4 = 194.2 g/mol
Mass of K₂CrO₄ = (4.5 mol) × (194.2 g/mol) = 874 g

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OR:
(3.75 mol K₂CrO₄ / 1 L solution) × (1.2 L solution) × (194.2 g K₂CrO₄ / 1 mol K₂CrO₄)
= 874 g K₂CrO₄