Why would mixing decrease the enthalpy?

Thread starter gfd43tg
Start date May 11, 2014
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decrease Enthalpy Mixing

In summary, mixing decreases the enthalpy of a substance by increasing the randomness of particles and breaking attractive forces between them. However, in some cases, mixing can actually increase the enthalpy if it requires energy. Factors such as intermolecular forces, temperature, pressure, and number of particles can influence the enthalpy change during mixing. The stability of a system can also be affected by mixing, with a decrease in enthalpy leading to increased stability and an increase in enthalpy leading to decreased stability.

May 11, 2014

gfd43tg

Gold Member

Hello

I am curious, why is the heat if mixing negative? Why would mixing decrease the enthalpy?

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May 12, 2014

gfd43tg

Gold Member

Just read that hears of mixing can be either endothermic or exothermic. What would be the reasons for why it could go either way?

1. Why does mixing decrease the enthalpy?

Mixing decreases the enthalpy because it increases the randomness of the particles in a system, leading to a decrease in the system's energy and therefore its enthalpy. This is known as the mixing entropy effect.

2. How does mixing affect the enthalpy of a substance?

Mixing decreases the enthalpy of a substance by breaking the attractive forces between particles and increasing the disorder of the system. This results in a decrease in the overall energy of the system, leading to a decrease in enthalpy.

3. Can mixing ever increase the enthalpy?

In some cases, mixing can actually increase the enthalpy of a substance. This occurs when the mixing process requires energy, such as when mixing two substances with different temperatures or when mixing substances that undergo a chemical reaction.

4. What factors can influence the enthalpy change during mixing?

The enthalpy change during mixing can be influenced by various factors, such as the nature and strength of the intermolecular forces between particles, the temperature and pressure of the system, and the number of particles involved in the mixing process.

5. How does mixing affect the stability of a system?

Mixing can affect the stability of a system by either increasing or decreasing its enthalpy. If mixing decreases the enthalpy, the system becomes more stable as it has lower energy and is in a more favorable state. However, if mixing increases the enthalpy, the system becomes less stable as it requires more energy and is in a less favorable state.