- #1
PPonte
Why does the solubility of KNO3, in water, rises with increasing temperature and the solubility of Na2SO4 descreases? 
Thank you.
Thank you.
Understanding Solubility: KNO3 and Na2SO4 in Water
- Thread starter PPonte
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In summary, the solubility of KNO3 in water increases with increasing temperature due to the global endoenergetic nature of its dissolution process. Conversely, the solubility of Na2SO4 decreases with increasing temperature due to its globally exoenergetic dissolution process. This is because the energy consumed in the first phase of dissolution is greater for KNO3 and less for Na2SO4, resulting in different overall energies for their dissolution.
- #2
Gokul43201
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What are your thoughts ?
We can't help you unless you help yourself.
We can't help you unless you help yourself.
- #3
PPonte
I am sorry. I usually help people who do not present their thoughts, I never remeber those rules.
Here are my thoughts:
1. The dissolution of a salt involves two phases. First, the separation of the ions, which is endoenergetic because involves breaking of ionic bonds and, second, the solvatation, in this case, an hydration since the solvent is water, which is exoenergetic.
2. If the energy consumed in the first phase is greater than the energy freed in the second phase, the dissolution of the salt is globally endoenergetic. If the energy consumed in the first phase is minor than the energy freed in the second phase, the dissolution of the salt is globally exoenergetic.
Conclusion: I think, then, that the dissolution of KNO3 is globally endoenergetic, so rises with increasing temperature, and the dissolution of Na2SO4 is globally exoenergetic so decreases with increasing temperature.
Am I right?
Here are my thoughts:
1. The dissolution of a salt involves two phases. First, the separation of the ions, which is endoenergetic because involves breaking of ionic bonds and, second, the solvatation, in this case, an hydration since the solvent is water, which is exoenergetic.
2. If the energy consumed in the first phase is greater than the energy freed in the second phase, the dissolution of the salt is globally endoenergetic. If the energy consumed in the first phase is minor than the energy freed in the second phase, the dissolution of the salt is globally exoenergetic.
Conclusion: I think, then, that the dissolution of KNO3 is globally endoenergetic, so rises with increasing temperature, and the dissolution of Na2SO4 is globally exoenergetic so decreases with increasing temperature.
Am I right?
- #4
Gokul43201
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Perfectly.
PS : Please do not help folks that show no original effort. It is rarely helpful to the student in the long run.
PS : Please do not help folks that show no original effort. It is rarely helpful to the student in the long run.
1. What is solubility?
Solubility refers to the ability of a substance, known as the solute, to dissolve in a solvent to form a homogeneous mixture. This process is dependent on various factors, such as temperature, pressure, and the nature of the solute and solvent.
2. How is solubility measured?
Solubility is typically measured in terms of the maximum amount of solute that can dissolve in a given amount of solvent at a specific temperature and pressure. This is known as the solubility limit or saturation point.
3. What is the relationship between temperature and solubility?
In general, the solubility of most solids in liquid solvents increases with increasing temperature. This is because the kinetic energy of the particles increases, leading to more collisions between solute and solvent molecules and thus, a higher likelihood of dissolution. However, there are some exceptions to this rule, such as the solubility of gases in water, which decreases with increasing temperature.
4. How does the nature of the solute and solvent affect solubility?
The nature of the solute and solvent can greatly influence the solubility of a substance. For example, polar solutes tend to dissolve in polar solvents, while nonpolar solutes dissolve in nonpolar solvents. Additionally, the size and shape of the molecules, as well as any intermolecular forces present, can also impact solubility.
5. How does the solubility of KNO3 and Na2SO4 in water compare?
KNO3, or potassium nitrate, is more soluble in water than Na2SO4, or sodium sulfate. At 25°C, the solubility of KNO3 in water is approximately 31 g per 100 mL of water, while the solubility of Na2SO4 is only about 10 g per 100 mL of water. This is due to the differences in the chemical structures and polarities of the two compounds.
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