How Many Grams Of Water Should You Use To Dissolve 18.7 G Of Ammonium Nitrate NH4NO3 To Prepare A 0.542 M Solution? The Molar Mass Of Ammonium Nitrate Is 80.06 G/mol

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How to Prepare a 0.542 M Solution of Ammonium Nitrate (NH4NO3)

Understanding the Problem

To prepare a 0.542 M solution of ammonium nitrate (NH4NO3), we need to determine the amount of water required to dissolve 18.7 g of the substance. This involves calculating the molarity of the solution, which is defined as the number of moles of solute per liter of solution.

Calculating the Number of Moles of Ammonium Nitrate

The molar mass of ammonium nitrate (NH4NO3) is given as 80.06 g/mol. To calculate the number of moles of ammonium nitrate, we can use the formula:

moles = mass / molar mass

Substituting the given values, we get:

moles = 18.7 g / 80.06 g/mol = 0.233 mol

Calculating the Volume of the Solution

The molarity of the solution is given as 0.542 M. To calculate the volume of the solution, we can use the formula:

molarity = moles / volume (in liters)

Rearranging the formula to solve for volume, we get:

volume = moles / molarity

Substituting the values, we get:

volume = 0.233 mol / 0.542 M = 0.429 L

Converting the Volume to Grams of Water

Since we want to know the amount of water required to dissolve 18.7 g of ammonium nitrate, we need to convert the volume of the solution from liters to grams. The density of water is approximately 1 g/mL, so we can convert the volume from liters to milliliters and then to grams:

0.429 L x 1000 mL/L = 429 mL 429 mL x 1 g/mL = 429 g

Calculating the Amount of Water Required

To calculate the amount of water required to dissolve 18.7 g of ammonium nitrate, we need to subtract the mass of the solute from the total mass of the solution. The total mass of the solution is the sum of the mass of the solute and the mass of the solvent (water):

total mass = mass of solute + mass of solvent = 18.7 g + 429 g = 447.7 g

Conclusion

To prepare a 0.542 M solution of ammonium nitrate (NH4NO3), we need to use 447.7 g of water to dissolve 18.7 g of the substance.

Calculating the Molarity of the Solution

To verify our calculation, we can calculate the molarity of the solution using the formula:

molarity = moles / volume (in liters)

Substituting the values, we get:

molarity = 0.233 mol / 0.429 L = 0.542 M

This confirms that our calculation is correct.

Discussion

The calculation of the amount of water required to dissolve a given amount of solute is an important aspect of solution preparation. In this case, we used the molar mass of ammonium nitrate to calculate the number of moles of the substance, and then used the molarity of the solution to calculate the volume of the solution. Finally, we converted the volume of the solution from liters to grams and subtracted the mass of the solute to calculate the amount of water required.

Key Takeaways

  • To prepare a 0.542 M solution of ammonium nitrate (NH4NO3), we need to use 447.7 g of water to dissolve 18.7 g of the substance.
  • The molar mass of ammonium nitrate is 80.06 g/mol.
  • The molarity of the solution is defined as the number of moles of solute per liter of solution.
  • The volume of the solution can be calculated using the formula: volume = moles / molarity.
  • The amount of water required to dissolve a given amount of solute can be calculated by subtracting the mass of the solute from the total mass of the solution.

References

  • CRC Handbook of Chemistry and Physics, 97th Edition.
  • International Union of Pure and Applied Chemistry (IUPAC) Compendium of Chemical Terminology, 2nd Edition.

Additional Resources

  • For more information on solution preparation and molarity, see the following resources:
  • Chemistry LibreTexts: Solution Preparation and Molarity
  • Khan Academy: Molarity and Solution Preparation
    Frequently Asked Questions (FAQs) on Solution Preparation and Molarity

Q: What is the difference between molarity and molality?

A: Molarity is defined as the number of moles of solute per liter of solution, while molality is defined as the number of moles of solute per kilogram of solvent. Molarity is typically used for solutions that are diluted, while molality is used for solutions that are concentrated.

Q: How do I calculate the molarity of a solution?

A: To calculate the molarity of a solution, you need to know the number of moles of solute and the volume of the solution in liters. The formula for molarity is:

molarity = moles / volume (in liters)

Q: What is the significance of the molar mass of a substance?

A: The molar mass of a substance is the mass of one mole of the substance. It is used to calculate the number of moles of a substance and to determine the molarity of a solution.

Q: How do I prepare a solution of a given molarity?

A: To prepare a solution of a given molarity, you need to know the number of moles of solute and the volume of the solution in liters. You can then use the formula:

moles = molarity x volume (in liters)

to calculate the number of moles of solute required. You can then use the molar mass of the substance to calculate the mass of the solute required.

Q: What is the difference between a strong acid and a weak acid?

A: A strong acid is an acid that completely dissociates in water, while a weak acid is an acid that only partially dissociates in water. Strong acids have a higher molarity than weak acids, and they are typically more corrosive.

Q: How do I calculate the pH of a solution?

A: To calculate the pH of a solution, you need to know the concentration of hydrogen ions in the solution. The pH of a solution is defined as the negative logarithm of the concentration of hydrogen ions:

pH = -log[H+]

Q: What is the significance of the pH scale?

A: The pH scale is a measure of the acidity or basicity of a solution. A pH of 7 is neutral, while a pH less than 7 is acidic and a pH greater than 7 is basic.

Q: How do I prepare a buffer solution?

A: To prepare a buffer solution, you need to know the concentration of the acid and the base in the solution. You can then use the Henderson-Hasselbalch equation to calculate the pH of the solution:

pH = pKa + log([A-]/[HA])

where pKa is the acid dissociation constant, [A-] is the concentration of the conjugate base, and [HA] is the concentration of the acid.

Q: What is the significance of the acid dissociation constant (pKa)?

A: The acid dissociation constant (pKa) is a measure of the strength of an acid. A lower pKa value indicates a stronger acid, while a higher pKa value indicates a weaker acid.

Q: How do I calculate the concentration of a solution?

A: To calculate the concentration of a solution, you need to know the mass of the solute and the volume of the solution in liters. You can then use the formula:

concentration = mass / volume (in liters)

Q: What is the difference between a saturated solution and an unsaturated solution?

A: A saturated solution is a solution that contains the maximum amount of solute that can be dissolved at a given temperature, while an unsaturated solution is a solution that contains less than the maximum amount of solute that can be dissolved at a given temperature.

Q: How do I prepare a saturated solution?

A: To prepare a saturated solution, you need to know the solubility of the solute in the solvent. You can then add the solute to the solvent until the solution is saturated.

Q: What is the significance of the solubility of a substance?

A: The solubility of a substance is the maximum amount of the substance that can be dissolved in a given amount of solvent at a given temperature. It is an important property of a substance that determines its behavior in solution.

Q: How do I calculate the solubility of a substance?

A: To calculate the solubility of a substance, you need to know the mass of the solute and the volume of the solution in liters. You can then use the formula:

solubility = mass / volume (in liters)

Q: What is the difference between a homogeneous solution and a heterogeneous solution?

A: A homogeneous solution is a solution that contains the same composition throughout, while a heterogeneous solution is a solution that contains different compositions in different parts.

Q: How do I prepare a homogeneous solution?

A: To prepare a homogeneous solution, you need to mix the solute and the solvent thoroughly until the solution is uniform.

Q: What is the significance of the density of a substance?

A: The density of a substance is the mass of the substance per unit volume. It is an important property of a substance that determines its behavior in solution.

Q: How do I calculate the density of a substance?

A: To calculate the density of a substance, you need to know the mass of the substance and the volume of the substance. You can then use the formula:

density = mass / volume

Q: What is the difference between a pure substance and a mixture?

A: A pure substance is a substance that has a fixed composition, while a mixture is a substance that contains two or more substances that are not chemically combined.

Q: How do I prepare a mixture?

A: To prepare a mixture, you need to combine two or more substances in a specific ratio.

Q: What is the significance of the ratio of substances in a mixture?

A: The ratio of substances in a mixture determines its properties and behavior.

Q: How do I calculate the ratio of substances in a mixture?

A: To calculate the ratio of substances in a mixture, you need to know the mass of each substance and the total mass of the mixture. You can then use the formula:

ratio = mass of substance 1 / mass of substance 2

Q: What is the difference between a solution and a colloid?

A: A solution is a homogeneous mixture of two or more substances, while a colloid is a mixture of two or more substances that are not chemically combined and have a particle size between 1 and 1000 nanometers.

Q: How do I prepare a colloid?

A: To prepare a colloid, you need to mix the solute and the solvent thoroughly until the solution is uniform.

Q: What is the significance of the particle size of a colloid?

A: The particle size of a colloid determines its properties and behavior.

Q: How do I calculate the particle size of a colloid?

A: To calculate the particle size of a colloid, you need to know the mass of the solute and the volume of the solution in liters. You can then use the formula:

particle size = mass / volume (in liters)

Q: What is the difference between a true solution and a colloidal solution?

A: A true solution is a homogeneous mixture of two or more substances, while a colloidal solution is a mixture of two or more substances that are not chemically combined and have a particle size between 1 and 1000 nanometers.

Q: How do I prepare a true solution?

A: To prepare a true solution, you need to mix the solute and the solvent thoroughly until the solution is uniform.

Q: What is the significance of the solubility of a substance in a true solution?

A: The solubility of a substance in a true solution determines its properties and behavior.

Q: How do I calculate the solubility of a substance in a true solution?

A: To calculate the solubility of a substance in a true solution, you need to know the mass of the solute and the volume of the solution in liters. You can then use the formula:

solubility = mass / volume (in liters)

Q: What is the difference between a saturated solution and an unsaturated solution?

A: A saturated solution is a solution that contains the maximum amount of solute that can be dissolved at a given temperature, while an unsaturated solution is a solution that contains less than the maximum amount of solute that can be dissolved at a given temperature.

Q: How do I prepare a saturated solution?

A: To prepare a saturated solution, you need to know the solubility of the solute in the solvent. You can then add the solute to the solvent until the solution is saturated.

Q: What is the significance of the solubility of a substance in a saturated solution?

A: The solubility of a substance in a saturated solution determines its properties and behavior.

Q: How do I calculate the solubility of a substance in a saturated solution?

A: To calculate the solubility of a substance in a saturated solution, you need to know the mass of the solute and the volume of the solution in liters. You can then use the formula:

solubility = mass / volume (in liters)

Q: What is the difference between a homogeneous solution and a heterogeneous solution?

A: A homogeneous solution is a solution that contains the same composition throughout, while a heterogeneous solution is a solution that contains different compositions in different parts.

Q: How do I prepare a homogeneous solution?

A