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The equilibrium constant is increasing with T for endothermic reactions.

$$ \frac{\text{d} (\ln {K}) }{ \text{d} T} = \dfrac {\Delta_r H}{RT^2}$$$$ \frac{\text{d} (\ln {K}) }{ \text{d} T} = \dfrac {\Delta_r H^{\circ}}{RT^2}$$

For a small enough temperature interval, where $\Delta_r H$ can be approximated as being constant:

$$ \ln \left({\frac{K_{T_2}}{K_{T_1}}}\right) = \dfrac {\Delta_r H^{\circ}}{R}\left(\frac{1}{T_1} - \frac{1}{T_2}\right)$$

Its value is pressure independent, at least for ideal gases, if expressed in partial pressures.

But the reaction quotient, (formally the same expression as for the equilibrium constant, but for any reaction state), decreases with increasing pressure, if volume of reactants is bigger than of products.

$$K = \frac{p_\text{B, eq} }{ p_\text{A, eq}^2}$$

$$Q = \frac{p_\text{B} }{ p_\text{A}^2}$$

For doubled pressure:

$$Q_2 = \frac{2 \cdot p_\text{B} }{ (2 \cdot p_\text{A})^2} = \frac{Q}{2}$$

Simultaneous changes of both temperature and pressure changes both values $K$ and $Q$.

  • If $Q \lt K$ then the forward net reaction is ongoing.
  • If $Q \gt K$ then the backward net reaction is ongoing.

The equilibrium constant is increasing with T for endothermic reactions.

$$ \frac{\text{d} (\ln {K}) }{ \text{d} T} = \dfrac {\Delta_r H}{RT^2}$$

Its value is pressure independent, at least for ideal gases, if expressed in partial pressures.

But the reaction quotient, (formally the same expression as for the equilibrium constant, but for any reaction state), decreases with increasing pressure, if volume of reactants is bigger than of products.

$$K = \frac{p_\text{B, eq} }{ p_\text{A, eq}^2}$$

$$Q = \frac{p_\text{B} }{ p_\text{A}^2}$$

For doubled pressure:

$$Q_2 = \frac{2 \cdot p_\text{B} }{ (2 \cdot p_\text{A})^2} = \frac{Q}{2}$$

Simultaneous changes of both temperature and pressure changes both values $K$ and $Q$.

  • If $Q \lt K$ then the forward net reaction is ongoing.
  • If $Q \gt K$ then the backward net reaction is ongoing.

The equilibrium constant is increasing with T for endothermic reactions.

$$ \frac{\text{d} (\ln {K}) }{ \text{d} T} = \dfrac {\Delta_r H^{\circ}}{RT^2}$$

For a small enough temperature interval, where $\Delta_r H$ can be approximated as being constant:

$$ \ln \left({\frac{K_{T_2}}{K_{T_1}}}\right) = \dfrac {\Delta_r H^{\circ}}{R}\left(\frac{1}{T_1} - \frac{1}{T_2}\right)$$

Its value is pressure independent, at least for ideal gases, if expressed in partial pressures.

But the reaction quotient, (formally the same expression as for the equilibrium constant, but for any reaction state), decreases with increasing pressure, if volume of reactants is bigger than of products.

$$K = \frac{p_\text{B, eq} }{ p_\text{A, eq}^2}$$

$$Q = \frac{p_\text{B} }{ p_\text{A}^2}$$

For doubled pressure:

$$Q_2 = \frac{2 \cdot p_\text{B} }{ (2 \cdot p_\text{A})^2} = \frac{Q}{2}$$

Simultaneous changes of both temperature and pressure changes both values $K$ and $Q$.

  • If $Q \lt K$ then the forward net reaction is ongoing.
  • If $Q \gt K$ then the backward net reaction is ongoing.
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Poutnik
  • 42.7k
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  • 108

The equilibrium constant is increasing with T for endothermic reactions.

$$ \frac{\text{d} (\ln {K}) }{ \text{d} T} = \dfrac {\Delta_r H}{RT^2}$$

Its value is pressure independent, at least for ideal gases, if expressed in partial pressures.

But the reaction quotient, (formally the same expression as for the equilibrium constant, but for any reaction state), decreases with increasing pressure, if volume of reactants is bigger than of products.

$$K = \frac{p_\text{B, eq} }{ p_\text{A, eq}^2}$$

$$Q = \frac{p_\text{B} }{ p_\text{A}^2}$$

For doubled pressure:

$$Q_2 = \frac{2 \cdot p_\text{B} }{ (2 \cdot p_\text{A})^2} = \frac{Q}{2}$$

Simultaneous changes of both temperature and pressure changes both values $K$ and $Q$.

  • If $Q \lt K$ then the forward net reaction is ongoing.
  • If $Q \gt K$ then the backward net reaction is ongoing.

The equilibrium constant is increasing with T for endothermic reactions.

$$ \frac{\text{d} (\ln {K}) }{ \text{d} T} = \dfrac {\Delta_r H}{RT^2}$$

Its value is pressure independent, at least for ideal gases, if expressed in partial pressures.

But the reaction quotient, (formally the same expression as for the equilibrium constant, but for any reaction state), decreases with increasing pressure, if volume of reactants is bigger than of products.

$$K = \frac{p_\text{B, eq} }{ p_\text{A, eq}^2}$$

$$Q = \frac{p_\text{B} }{ p_\text{A}^2}$$

The equilibrium constant is increasing with T for endothermic reactions.

$$ \frac{\text{d} (\ln {K}) }{ \text{d} T} = \dfrac {\Delta_r H}{RT^2}$$

Its value is pressure independent, at least for ideal gases, if expressed in partial pressures.

But the reaction quotient, (formally the same expression as for the equilibrium constant, but for any reaction state), decreases with increasing pressure, if volume of reactants is bigger than of products.

$$K = \frac{p_\text{B, eq} }{ p_\text{A, eq}^2}$$

$$Q = \frac{p_\text{B} }{ p_\text{A}^2}$$

For doubled pressure:

$$Q_2 = \frac{2 \cdot p_\text{B} }{ (2 \cdot p_\text{A})^2} = \frac{Q}{2}$$

Simultaneous changes of both temperature and pressure changes both values $K$ and $Q$.

  • If $Q \lt K$ then the forward net reaction is ongoing.
  • If $Q \gt K$ then the backward net reaction is ongoing.
Source Link
Poutnik
  • 42.7k
  • 3
  • 50
  • 108

The equilibrium constant is increasing with T for endothermic reactions.

$$ \frac{\text{d} (\ln {K}) }{ \text{d} T} = \dfrac {\Delta_r H}{RT^2}$$

Its value is pressure independent, at least for ideal gases, if expressed in partial pressures.

But the reaction quotient, (formally the same expression as for the equilibrium constant, but for any reaction state), decreases with increasing pressure, if volume of reactants is bigger than of products.

$$K = \frac{p_\text{B, eq} }{ p_\text{A, eq}^2}$$

$$Q = \frac{p_\text{B} }{ p_\text{A}^2}$$