How much heat is released during the formation of 3.18 mol hcl(g) in this reaction: h2(g)+cl2(g) → 2hcl(g) with a ∆h of -184.6 kj. express your answer in kj?

To find the heat released during the formation of 3.18 mol of HCl(g), you should first look at the stoichiometry of the balanced chemical equation and the given enthalpy change (∆H). The balanced equation provided is:

H2(g) + Cl2(g) → 2HCl(g)

This reaction indicates that 1 mole of H2 reacts with 1 mole of Cl2 to produce 2 moles of HCl. The enthalpy change given for this reaction is -184.6 kJ. Since the enthalpy change is negative, it means that the reaction releases heat (it's exothermic).

The enthalpy change corresponds to the formation of 2 moles of HCl from H2 and Cl2. To calculate the heat released for the formation of 3.18 moles of HCl, use the ratio of moles from the given reaction:

(3.18 mol HCl) x (-184.6 kJ / 2 mol HCl) = Y kJ

Now calculate the value:

Y = 3.18 x (-184.6) / 2 Y = -294.868 kJ

Therefore, the heat released during the formation of 3.18 mol HCl(g) is 294.868 kJ. Since heat is released, the value is negative, indicating an exothermic reaction.

Extra: In chemistry, the heat or energy change that occurs during a chemical reaction is called enthalpy change (∆H). This is an important concept when studying reactions, as it helps predict whether a reaction will release heat to its surroundings (exothermic) or absorb heat from its surroundings (endothermic).

For exothermic reactions, ∆H is negative because energy is released when products form. Conversely, for endothermic reactions, ∆H is positive because energy is absorbed to break the bonds of the reactants.

When working with enthalpy changes, it's important to consider the stoichiometry of the chemical equation, which tells you the relative amounts of reactants and products involved. It allows for the calculation of energy released or absorbed in a reaction based on the number of moles of chemicals reacting or produced.

In this example, we calculated the amount of energy for a specific number of moles that didn't exactly match the balanced equation. By using stoichiometry, you can scale up or down the reported ∆H for the reaction to determine the energy change for any given amount of reactants or products. This is a fundamental aspect of chemical thermodynamics and is used for calculating energy changes in various types of reactions.