When discussing solutions like a 50% NaCl or a 35% ethylene glycol solution, it's crucial to clarify whether the percentage refers to weight/volume (w/v) or volume/volume (v/v). A 50% (w/v) NaCl solution indicates 50 grams of NaCl dissolved in 100 mL of water. In contrast, a 35% ethylene glycol solution typically means 35 mL of ethylene glycol combined with 65 mL of water, totaling 100 mL of solution. While it's noted that volumes do not always add up perfectly, for practical laboratory purposes, minor discrepancies are generally acceptable. The interpretation often leans towards understanding the percentage as the amount of solute in relation to the total solution.
