A spontaneous reaction has a negative delta G and a large K value. A

**non**-spontaneous reaction has a positive delta G and a small K value. When delta G is equal to zero and K is around one, the reaction is at equilibrium.What is the formula of entropy?

In statistical mechanics, Boltzmann's

**equation**is a probability**equation**relating the**entropy**S of an ideal gas to the quantity W, the number of real microstates corresponding to the gas' macrostate: (1) where k_{B}is the Boltzmann constant (also written as simply k) and equal to 1.38065 × 10^{−}^{23}J/K.1

## What is K at equilibrium?

When we know the numerical value of the

**equilibrium**constant, we can make certain judgments about the extent of the chemical reaction.**K**> 1. If**K**is larger than 1, the mixture contains mostly products.**K**< 1. If**K**is less than 1, the mixture contains mostly reactants.2

## Is Gibbs free energy zero at equilibrium?

**Gibbs free energy**is a measure of how much "potential" a reaction has left to do a net "something." So if the

**free energy**is

**zero**, then the reaction is at

**equilibrium**, an no more work can be done. It may be easier to see this using an alternative form of the the

**Gibbs free energy**, such as Δ G = − T Δ S .

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## Is entropy state function?

A

**state function**describes the equilibrium**state**of a system and thus also describes the type of system. For example, internal energy, enthalpy, and**entropy**are**state**quantities because they describe quantitatively an equilibrium**state**of a thermodynamic system, irrespective of how the system arrived in that**state**.4

## How do you calculate enthalpy?

Use the

**formula**∆H = m x s x ∆T to solve. Once you have m, the mass of your reactants, s, the specific heat of your product, and ∆T, the temperature change from your reaction, you are prepared to find the**enthalpy**of reaction. Simply plug your values into the**formula**∆H = m x s x ∆T and multiply to solve.5

## Is the reaction spontaneous when Delta G is negative?

Because this reaction has a positive

**Delta G**it will be non-**spontaneous**as written. Because D**G**is a measure of how favorable a reaction is, it also relates to the equilibrium constant. A reaction with a**negative**D**G**, is very favorable, so it has a large K.6

## What is the unit of Delta G?

Chemists normally measure

**energy**(both enthalpy and Gibbs free**energy**) in kJ mol^{-}^{1}(kilojoules per**mole**) but measure entropy in J K^{-}^{1}mol^{-}^{1}(joules per**kelvin**per**mole**). So it is necessary to convert the units – usually by dividing the entropy values by 1000 so that they are measured in kJ K^{-}^{1}mol^{-}^{1}.7

## What is the delta S?

**Delta S**is entropy. It's a measurement of randomness or disorder. Notice I have

**deltas**in front of these. That's because we typically talk about changes, reactions or processes that actually happen in Chemistry.

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## What is the equilibrium constant?

Definition of

**equilibrium constant**. : a number that expresses the relationship between the amounts of products and reactants present at**equilibrium**in a reversible chemical reaction at a given temperature.9

## When a reaction is spontaneous?

By examining these two factors: entropy and whether or not the

**reaction**is exothermic or endothermic, we can tell if a**reaction is spontaneous**using the Gibbs Free Energy equation: According to this equation, if the free energy, G, of the system is negative, then the**reaction is spontaneous**.10

## What is the meaning of Delta S?

**Delta S**is entropy. It's a measurement of randomness or disorder. Well H is the measurement of heat or energy, but it's a measurement of the transfer of heat or energy. We cannot decipher how much heat or energy something has in it. We can only measure the change it undergoes through a chemical process.

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## What is r in Delta G equation?

In this

**equation**:**R**= 8.314 J mol^{-}^{1}K^{-}^{1}or 0.008314 kJ mol^{-}^{1}K^{-}^{1}. T is the temperature on the Kelvin scale.12

## What is Delta G not?

Standard condition means the pressure 1 bar and Temp 298K, ΔG° is the measure of Gibbs Free Energy (

**G**) - The energy associated with a chemical reaction that can be used to do work change at 1 bar and 298 K,**delta G**"**naught**" (**not not**) is**NOT**necessarily a non-zero value.13

## How is free energy related to entropy and enthalpy?

**Gibbs free energy**combines

**enthalpy and entropy**into a single value.

**Gibbs free energy**is the

**energy**associated with a chemical reaction that can do useful work. It equals the

**enthalpy**minus the product of the temperature and

**entropy**of the system. If ΔG is positive, then the reaction is non-spontaneous.

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## What is Delta G prime?

Enthalpy, denoted H and measured in J/mol, is total energy. We define ΔG

^{0}' (pronounced “**delta G**naught**prime**”) as the free energy change of a reaction under “standard conditions” which are defined as: All reactants and products are at an initial concentration of 1.0M. Pressure of 1.0 atm.15

## What is the Q in chemistry?

When the reaction is not in equilibrium, we can determine its state by calculating the reaction quotient (

**Q**), which relates the concentrations of products to reactants at any time. The reaction quotient is useful in determining the direction in which the reaction is moving - toward or away from**chemical**equilibrium.16

## What is a spontaneous chemical reaction?

A

**reaction**is said to be**spontaneous**if it occurs without being driven by some outside force. There are two driving forces for all chemical**reactions**. The first is enthalpy, and the second is entropy.**Spontaneous reactions**occur without outside intervention.17

## What causes a spontaneous reaction?

Gibbs free energy is the amount of energy left over after a chemical

**reaction**has taken place. A**spontaneous reaction**may involve an increase or decrease in enthalpy, it may involve an increase or decrease in entropy, but it will always involve a decrease in free energy that is a negative ΔG.18

## Is KEQ 1 at equilibrium?

If

**Keq**is much greater than**1**(For example if**Keq**= 10^{3}), then the position of**equilibrium**is to the right; more products are present at**equilibrium**. If**Keq**=**1**, then the position of**equilibrium**is in the center, the amount of products is roughly equal to the amount of reactants at**equilibrium**.19

## Can the equilibrium constant ever be a negative number?

If you are only examining a single reaction, then the answer is no. Given that the pre-exponential factor of the Arrhenius equation is always positive (otherwise, you would potentially have a rate

**constant**of 0, meaning the reaction never occurs), the rate**constant**is never**negative**.