Answer to Question #341962 in General Chemistry for Carrot

Question

ESSAY.

Water, compared to other substances, has one of the highest specific heat values. What is the advantage of this fact for the human body?

Direction: Solve the following problems. Attach your solutions.

1. Calculate the standard enthalpy change ΔH°, for the following reaction:

2CH3OH (l) + 3O2 (g) --> 2CO2 (g) + 2H2O (g)

Given: CH3OH (l) -------> ΔHf° = -238.7 kJ

CO2 (g) -------> ΔHf° = -393.5 kJ

H2O (l) -------> ΔHf° = -285.8 kJ

Answer 1

Specific heat is the quantity defined by the amount of heat needed to raise the temperature of 1 gram of a substance 1 degree Celsius (°C). Water has a high specific heat, meaning it takes more energy to increase the temperature of water compared to other substances. The human body contains more than 50 % of water, so it helps to control the body temperature and prevent it from overheating.

1. $2CH_3OH (l) + 3O_2 (g) = 2CO_2 (g) + 2H_2O (g)$

$\Delta H^0 = \sum \Delta H_f^0(prod) - \sum \Delta H_f^0(react)$

$\Delta H^0 = 2\Delta H_f^0(CO_2) + 2\Delta H_f^0(H_2O) -$

$- 2\Delta H_f^0(CH_3OH) +3 \Delta H_f^0(O_2)$

$\Delta H^0=2\times(-393.5) + 2 \times (-285.8) - 2\times (-238.7) +3\times 0$

$\Delta H^0=-881.2 kJ$