A concentrated nitric acid solution has a density of 1.41 g/mL at 25°C and is 15.8 M.What is the percent by mass of HNO_{3 in the solution?} A) 70.6% HNO_{3 by mass} B) 1.12% HNO_{3 by mass} C) 0.895% HNO_{3 by mass} D) 1.77% HNO_{3 by mass} E) 44.7% HNO_{3 by mass}

Question

Quizplus · Accepted Answer

To find the percent by mass of HNO3 in the solution, first calculate the mass of 1 liter of the solution using its density (1.41 g/mL). For 1 L (1000 mL), the mass is 1.41 g/mL * 1000 mL = 1410 g. Next, calculate the mass of HNO3 in 1 L of solution using its molarity (15.8 M), which means 15.8 moles of HNO3 per liter. The molar mass of HNO3 is approximately 63.01 g/mol, so the mass of HNO3 in 1 L is 15.8 moles * 63.01 g/mol = 995.958 g. The percent by mass of HNO3 is then (995.958 g / 1410 g) * 100% ≈ 70.6%.

A Concentrated Nitric Acid Solution Has a Density of 1