CHAPTER 5: THERMOCHEMISTRY

Internal energy

Internal energy

________ is an example of a state function, a property of a system that is determined by specifying the systems condition, or state (in terms of temperature, pressure, and so forth)

Petroleum

________ is a liquid composed of hundreds of compounds, most of which are hydrocarbons, with the remainder being chiefly organic compounds containing sulfur, nitrogen, or oxygen.

Fossil fuels

________ and nuclear energy are nonrenewable sources of energy- they are limited resources that we are consuming at a much greater rate than they can be regenerated.

symbol ∆

The ________ is commonly used to denote change.

Pressure P

________ is always either a positive number or zero.

chemical reaction

In a(n) ________, the initial state of the system refers to the reactants and the final state refers to the products.

Natural gas

________ consists of gaseous hydrocarbons, compounds of hydrogen and carbon.

Glucose

________ is soluble in blood, and in the human body it is known as blood sugar.

real compounds

In ________, repulsions between core electrons place a lower limit on how closely the ions can approach each other.

∆H

Pressure can be controlled to directly measure ________ in various processes, including those in solution.

Energy

________ is released when chemical bonds are formed;

symbol Σ

The ________ (sigma) means "the sum of, "and n and m are the stoichiometric coefficients of the relevant chemical equation.

Fats

________ are well suited to serve as the bodys energy reserve for at least two reasons: (1) They are insoluble in water, which facilitates storage in the body, and (2) they produce more energy per gram than either proteins or carbohydrates, which makes them efficient energy sources on a mass basis.

Electricity

________ is typically generated by using a moving gas or liquid to turn a turbine that is connected to a generator, although there are some exceptions like solar cells.

carbohydrates

The ________ known as starches are decomposed in the intestines into glucose.

P

Where ________ is pressure and ∆V= Vfinal- Vinitial is the change in volume of the system.

Hesss law

________ provides a useful means of calculating energy changes that are difficult to measure directly.

Proteins

________ are used by the body mainly as building materials for organ walls, skin, hair, muscle, and so forth.

study of energy

The ________ and its transformations is known as thermodynamics (Greek: thérme,"- heat; "dynamis, "power)

Enthalpy

________ is an extensive property.

Energy changes

________ in chemical reactions can be used to transfer heat or do work.

Energy

________ is consumed when chemical bonds are broken.

Hesss law

________ states that if a reaction is carried out in a series of steps, ∆H for the overall reaction equals the sum of the enthalpy changes for the individual steps.

internal energy

When heat is added to a system or work is done on a system, its ________ increases.

exo

means "out of")