Unit 8 - Thermodynamics

Question 1

Heat

Answer 1

when energy is exchanged between thermodynamic systems by thermal interaction

Question 2

Combustion in respiration

Answer 2

slow combustion;
takes place at low temperatures;
often involves burning or metabolism of sugars, carbohydrates, and fats

Question 3

Work

Answer 3

transfer of energy by any process other than heat

Question 4

State function

Answer 4

property that has a unique value for a specified state of a system;
density, pressure, volume, temperature, total energy

Question 5

Path function

Answer 5

depends on the process or mechanism that takes a system from one set of conditions to another;
heat, work

Question 6

Change in enthalpy vs. change in internal intergy

Answer 6

enthalpy = energy of a system;
internal energy = intrinsic value of the sum of potential and kinetic energy;
values are equal when there is no work

Question 7

Standard formation reaction

Answer 7

formation of one mole of a substance in its standard state from the reference forms of its constituent elements

Question 8

Refrigerators

Answer 8

expansion of gases is used in refrigerators in order to move heat flow;
using CFCs as refrigerants is not ideal as they produce ozone gas

Question 9

Fossil fuels

Answer 9

a lot of energy is generated from burning fossil fuels as they have higher heats of combustion;
however, the are non-renewable and contribute to global warming