Question

which would be the best way to represent the concentration of a 1.75 m k₂cro₄ solution?
○ 1.75%
○ k₂cro₄ = 1.75 m
○ (k₂cro₄)
○ k₂cro₄, m

Explanation:

• 1.75% is a percentage concentration (mass/volume or mass/mass), not molarity (M), so the first option is incorrect.
• In chemistry, the square brackets around a solute formula denote its molar concentration (molarity). So $\ce{[K_2CrO_4] = 1.75\ M}$ properly represents the molarity of the $\ce{K_2CrO_4}$ solution.
• The notation $\ce{(K_2CrO_4)}$ is not a standard way to represent molarity; it could be ambiguous or used for other types of concentrations (like molality in some contexts, but not clearly here).
• The notation $\ce{K_2CrO_4, [M]}$ is not a standard or clear way to represent the molar concentration of the solute.

Answer:

B. $\boldsymbol{[K_2CrO_4] = 1.75\ M}$