Question

General Chemistry I! Workshop 8: Gibb's Free Energy Part I. (2 pts) Write down and balance chemical equations for (a) the reaction for burning 1 mole of hydrogen gas in oxygen to produce liquid water and (b) the reaction for burning 1 mole of liquid propane (CsHs) in oxygen to produce carbon dioxide gas and liquid water: (a) (b) Now look at the two reactions and discuss with yo group the following questions: (a) Which of these two methods of obtaining energy is better for the environment? (b) If you want to use these two fuels, hydrogen gas or liquid propane, directly which one of them is easier and safer to store and transport? Now write down your answers below and don't forget to justify them! (a) (b) so,1/K-mol AG, kJ/mol Thermodynamic data AH, kJ/mol Name H2(g) 02lg) H,O(g) H2O) CO,(g) 130.7 0.0 0.0 0.0 0.0 205.2 -228.6 -241.8 188.8 -285.8 -237.1 70.0 -393.5 -394.4 213.8 CaHa) -103.9 171.0

Answer 1

$H_2(g)+O_2(g) \to H_2O(l)$

Balance oxygen by adding coefficient 0.5 to dioxygen

$H_2(g)+0.5O_2(g) \to H_2O(l)$

$C_3H_8(l)+O_2(g) \to CO_2(g)+H_2O(l)$

Balance C atoms by adding coefficient 3 to carbon dioxide.

$C_3H_8(l)+O_2(g) \to 3CO_2(g)+H_2O(l)$

Balance H atoms by adding coefficient 4 to water

$C_3H_8(l)+O_2(g) \to 3CO_2(g)+4H_2O(l)$

Balance oxygen atoms by adding coefficient 5 to oxygen

$C_3H_8(l)+5O_2(g) \to 3CO_2(g)+4H_2O(l)$

(a) For the environment, burning hydrogen gas is better than burning liquid propane. In case of burning liquid propane, toxic carbon dioxide gas is obtained which pollutes environment. In case of burning, the product obtained is liquid water which is essential for life.

(b) Liquid propane is easier and safer to store and transport than hydrogen gas. A liquid is always easier to store and transport than a gas. Also hydrogen gas is highly inflammable.