Ask Question
10 October, 18:22

Aqueous concentrated nitric acid is 69% HNO3 by weight and has a density of 1.42 g/mL. What is the molarity of this solution?

What is the molality of the solution?

+3
Answers (1)
  1. 10 October, 18:29
    0
    The molality of the solution is 35.3 molal

    Explanation:

    Step 1: Data given

    69 w% HNO3

    density = 1.42 g/mL

    Molar mass of HNO3 = 63.01 g/mol

    Step 2: Calculate mass of HNO3

    Consider the volume of the solution = 1L = 1000 mL

    Mass = density * volume

    Mass HNO3 = 1.42 g/mL * 1000mL = 1420 grams

    if w% = 69% then the mass of this solution is:

    0.69 * 1420 = 979.8 grams

    Step 3: Calculate number of moles of HNO3

    Number of moles = mass / Molar mass

    Number of moles HNO3 = 979.8 grams / 63.01 g/mol = 15.55 moles

    Step 4: Calculate molarity

    Molarity = moles / volume

    Molarity = 15.55 moles / 1L = 15.55 M

    Step 5: Calculate mass of water

    Mass of water = Total mass of HNO3 solution - mass of 69% nitric solution

    Mass of water = 1420 - 979.9 = 440.2 grams

    Step 6: Calculate molality

    Molality = number of moles of HNO3 per 1000 g of water.

    Since there are 15.55 moles in 440.2 grams

    There are 15.55/440.2 = 0.0353 moles in 1 gram

    In 1000 g of water, there are 0.035 * 1000 = 35.3 moles

    The molality of the solution is 35.3 molal
Know the Answer?
Not Sure About the Answer?
Find an answer to your question 👍 “Aqueous concentrated nitric acid is 69% HNO3 by weight and has a density of 1.42 g/mL. What is the molarity of this solution? What is the ...” in 📗 Chemistry if the answers seem to be not correct or there’s no answer. Try a smart search to find answers to similar questions.
Search for Other Answers