91Ó°ÊÓ

For the reaction \(\mathrm{HgO}(s) \rightarrow \mathrm{Hg}(l)+\frac{1}{2} \mathrm{O}_{2}(g), \Delta H=+90.7 \mathrm{~kJ}:\) a. What quantity of heat is required to produce \(1 \mathrm{~mol}\) of mercury by this reaction? b. What quantity of heat is required to produce \(1 \mathrm{~mol}\) of oxygen gas by this reaction? c. What quantity of heat would be released in the following reaction as written? $$ 2 \mathrm{Hg}(l)+\mathrm{O}_{2}(g) \longrightarrow 2 \mathrm{HgO}(s) $$

The enthalpy of combustion of \(\mathrm{CH}_{4}(\mathrm{~g})\) when \(\mathrm{H}_{2} \mathrm{O}(l)\) is formed is \(-891 \mathrm{~kJ} / \mathrm{mol}\) and the enthalpy of combustion of \(\mathrm{CH}_{4}(\mathrm{~g})\) when \(\mathrm{H}_{2} \mathrm{O}(\mathrm{g})\) is formed is \(-803 \mathrm{~kJ} / \mathrm{mol} .\) Use these data and Hess's law to determine the enthalpy of vaporization for water.

The enthalpy change for a reaction is a state function and it is an extensive property. Explain.

Standard enthalpies of formation are relative values. What are \(\Delta H_{\mathrm{f}}^{\circ}\) values relative to?

Why is it a good idea to rinse your thermos bottle with hot water before filling it with hot coffee?

What is incomplete combustion of fossil fuels? Why can this be a problem?

Explain the advantages and disadvantages of hydrogen as an alternative fuel.

Calculate the kinetic energy of a baseball (mass \(=5.25 \mathrm{oz}\) ) with a velocity of \(1.0 \times 10^{2} \mathrm{mi} / \mathrm{h}\).

Calculate the kinetic energy of an object with a mass of \(1.0 \times\) \(10^{-5} \mathrm{~g}\) and a velocity of \(2.0 \times 10^{5} \mathrm{~cm} / \mathrm{s}\)

Which has the greater kinetic energy, an object with a mass of 2.0 \(\mathrm{kg}\) and a velocity of \(1.0 \mathrm{~m} / \mathrm{s}\) or an object with a mass of \(1.0 \mathrm{~kg}\) and a velocity of \(2.0 \mathrm{~m} / \mathrm{s}\) ?