Using the following thermochemical equations C2 H6( g)+(7)/(2) O2( g) →2 CO2( g)+3 H2 O(ℓ) ΔH=-1

step 1 In this question we're going to be focusing on three equations. The first equation we've got C2,

Using the following thermochemical equations C2...

Using the following thermochemical equations $$ \mathrm{C}_{2} \mathrm{H}_{6}(\mathrm{~g})+\frac{7}{2} \mathrm{O}_{2}(\mathrm{~g}) \rightarrow 2 \mathrm{CO}_{2}(\mathrm{~g})+3 \mathrm{H}_{2} \mathrm{O}(\ell) $$ $\Delta H=-1560 \mathrm{~kJ}$ $$ \begin{aligned} 2 \mathrm{C}_{2} \mathrm{H}_{2}(\mathrm{~g})+5 \mathrm{O}_{2}(\mathrm{~g}) \rightarrow 4 \mathrm{CO}_{2}(\mathrm{~g})+2 \mathrm{H}_{2} \mathrm{O}(\ell) \\ \mathrm{H}_{2}(\mathrm{~g})+\frac{1}{2} \mathrm{O}_{2}(\mathrm{~g}) \rightarrow \mathrm{H}_{2} \mathrm{O}(\ell) & \Delta H=-2599 \mathrm{~kJ} \\ & \Delta H=-286 \mathrm{~kJ} \end{aligned} $$ calculate $\Delta H$ for $$ \mathrm{C}_{2} \mathrm{H}_{2}(\mathrm{~g})+2 \mathrm{H}_{2}(\mathrm{~g}) \rightarrow \mathrm{C}_{2} \mathrm{H}_{6}(\mathrm{~g}) \quad \Delta H=? $$

Using the following thermochemical equations
$$
\mathrm{C}_{2} \mathrm{H}_{6}(\mathrm{~g})+\frac{7}{2} \mathrm{O}_{2}(\mathrm{~g}) \rightarrow 2 \mathrm{CO}_{2}(\mathrm{~g})+3 \mathrm{H}_{2} \mathrm{O}(\ell)
$$
$\Delta H=-1560 \mathrm{~kJ}$
$$
\begin{aligned}
2 \mathrm{C}_{2} \mathrm{H}_{2}(\mathrm{~g})+5 \mathrm{O}_{2}(\mathrm{~g}) \rightarrow 4 \mathrm{CO}_{2}(\mathrm{~g})+2 \mathrm{H}_{2} \mathrm{O}(\ell) \\
\mathrm{H}_{2}(\mathrm{~g})+\frac{1}{2} \mathrm{O}_{2}(\mathrm{~g}) \rightarrow \mathrm{H}_{2} \mathrm{O}(\ell) & \Delta H=-2599 \mathrm{~kJ} \\
& \Delta H=-286 \mathrm{~kJ}
\end{aligned}
$$
calculate $\Delta H$ for
$$
\mathrm{C}_{2} \mathrm{H}_{2}(\mathrm{~g})+2 \mathrm{H}_{2}(\mathrm{~g}) \rightarrow \mathrm{C}_{2} \mathrm{H}_{6}(\mathrm{~g}) \quad \Delta H=?
$$

Labs

Want to see this concept in action?

NEW

Explore this concept interactively to see how it behaves as you change inputs.

View Labs

Key Concepts

Thermochemical Equations

Thermochemical equations are chemical equations that include the enthalpy change associated with the reaction. They succinctly represent both the stoichiometry of the reactants and products and the energy changes that occur, providing critical information needed to understand and calculate reaction energetics.

Hess's Law

Hess's Law states that the total enthalpy change for a reaction is independent of the pathway taken, provided the initial and final conditions are the same. This principle allows one to combine, reverse, or multiply given thermochemical equations to derive the enthalpy change for a target reaction.

Reaction Manipulation

Reaction manipulation involves algebraic operations such as reversing, scaling, or combining chemical equations to obtain a desired overall reaction. When thermochemical equations are manipulated in this way, the corresponding enthalpy changes must be adjusted accordingly, ensuring that the calculated energy change for the resulting reaction is accurate.

Enthalpy Change

The enthalpy change (?H) of a reaction quantifies the heat energy absorbed or released during a chemical reaction at constant pressure. It is a fundamental thermodynamic quantity that provides insight into the energy efficiency and spontaneity of chemical processes.

Transcript

Please give Ace some feedback