Chapter 21, Problem 21.153P

a)

Interpretation Introduction

Interpretation:

Burning of $\text{1}\text{.00}\text{gal}$ gasoline to produce carbon-dioxide gas and water vapour, value of $\Delta {\text{H}}^{\circ }$ has to be calculated.

Concept Introduction:

The standard enthalpy of reaction is quantity of energy released or consumed when one mole of a substance is formed under standard conditions from its pure elemental form. It is denoted as ${\text{ΔH}}_{\text{rxn}}^{\text{°}}$.

$\begin{array}{l}{\text{ΔH}}_{\text{rxn}}^{\text{°}}={\text{ ΔH}}_{\text{p}}^{\text{°}}-{\text{ ΔH}}_{\text{r}}^{\text{°}}\\ {\text{ΔH}}_{\text{p}}^{\text{°}}\text{ = standard enthalpy of product}\\ {\text{ΔH}}_{\text{r}}^{\text{°}}\text{ = standard enthalpy of reactant}\end{array}$

b)

Interpretation Introduction

Interpretation:

Liters of ${\text{H}}_2$ required to burn the given quantity of energy has to be calculated.

Concept introduction:

Ideal gas: A hypothetical gas whose molecules occupy negligible space and have no interactions, and which consequently obeys the gas law exactly.

Ideal gas equation: An equation describes the relationship among the four variables P, V, T, and n.

$PV=nRT$

The unit of each term in the equation is,

Where, R is proportionality constant called gas constant $\left(atm.L/mol.K\right)$

  V is volume $\left(L\right)$

  N is number of moles $\left(moles\right)$

  P is Pressure $\left(atm\right)$

  T is temperature $\left(K\right)$

Standard temperature and pressure: The conditions ${\text{0}}^{\text{o}}\text{C}$ and $\text{1}\text{atm}$ are called standard atmospheric conditions.

c)

Interpretation Introduction

Interpretation:

For the amount of ${\text{H}}_2$ to produce the time required by electrolysis with a current of $\text{1}\text{.00}\text{×}{\text{10}}^{\text{3}}\text{A}\text{at 6}\text{.00}\text{V}$ has to be calculated.

d)

Interpretation Introduction

Interpretation:

Power required generating the amount of ${\text{H}}_{\text{2}}$ in kilowatt-hours has to be calculated.

e)

Interpretation Introduction

Interpretation:

The cost of producing the amount of ${\text{H}}_{\text{2}}$ equivalent to $\text{1}\text{.00}\text{gal}$ of gasoline has to be calculated.