Enthalpy is used to measure the total energy of a thermodynamic system. it may be in the form of heat or volume and increased by pressure. Enthalpy is a state function and extends the energy. Thus, the energy is resolved by the temperature, pressure, and composition of the system.

## Enthalpy Calculator

Enthalpy calculator is an online tool used for the purpose to calculate the change in enthalpy of a reaction. It takes the inputs and calculates the Enthalpy, so it very easy to solve the problems essential for Enthalpy calculations.

## Enthalpy Calculator

### Enthalpy Formula

Enthalpy (Qp) =∆E+P∆V

### Rules for Enthalpy calculator

**Step 1:**

You need to notice the value of change in internal energy, pressure and change in volume.

**Step2:**

Use the formula

**Enthalpy (Qp) =∆E+P∆V**

Where,

∆E=Change in Internal Energy= Internal Energy of Products (E_{p})-Internal Energy of Reactants(E_{r})

P=Pressure of the System

∆V=Change in Volume=Volume of Products (V_{p})-Volume of Reactants (V_{r}).

### Problems on Enthalpy Calculator

If the internal energy and volume of products and reactants are 234 joules, 130 joules, 20 cubic meters and 10 cubic meters, then calculate the respective enthalpy for a pressure of 200 pascals?

**Step 1**:

Given below that:

Internal Energy of Products (E_{p}) =234 joules

Internal Energy of Reactants(E_{r}) =130 joules

Volume of Products (V_{p})=20 cubic meters

Volume of Reactants (V_{r})=10 cubic meters

Pressure (P) =200 Pascal’s

Enthalpy (Q_{p}) =?

**Step 2:** We know that:

Enthalpy (Q_{p}) = ΔE + PΔV

Enthalpy (Q_{p}) = E_{p} – E_{r}+ P(V_{p} – V_{r})

Enthalpy (Q_{p}) = 234 J – 130 J + 200 Pa (20m^{3} – 10m^{3})

Enthalpy (Q_{p}) = 104 J + 200 Pa (10m3) = 2104 J

Answer:

The answer for the Enthalpy (Q_{p}) = 2104