3. The conservation of atoms in chemical reactions leads to the principle of conservation of matter and the ability to calculate the mass of products and reactants. As a basis for understanding this concept:
a. How to describe chemical reactions by writing balanced equations.
b. The quantity one mole is set by defining one mole of carbon 12 atoms to have a mass of exactly 12 grams.
c. One mole equals 6.02 x 10 to the 23rd particles (atoms or molecules).
d. How to determine the molar mass of a molecule from its chemical formula and a table of atomic masses and how to convert the mass of a molecular substance to moles, number of particles, or volume of gas at standard temperature and pressure.
e. How to calculate the masses of reactants and products in a chemical reaction from the mass of one of the reactants or products and the relevant atomic masses.
f. How to calculate percent yield in a chemical reaction.
g. How to identify reactions that involve oxidation and reduction and how to balance oxidation-reduction reactions.
GASES AND THEIR PROPERTIES
4. The kinetic molecular theory describes the motion of atoms and molecules and explains the properties of gases. As a basis for understanding this concept:
a. The random motion of molecules and their collisions with a surface create the observable pressure on that surface.
b. The random motion of molecules explains the diffusion of gases.
c. How to apply the gas laws to relations between the pressure, temperature, and volume of any amount of an ideal gas or any mixture of ideal gases.
d. The values and meanings of standard temperature and pressure (STP).
e. How to convert between the Celsius and Kelvin temperature scales.
f. There is no temperatire lower than 0 Kelvin.
g. The kinetic theory of gases relates the absolute temperature of a gas to the average kinetic energy of its molecules or atoms.
h. How to solve problems by using the ideal gas law in the form of PV=nRT
i. How to apply Dalton's law of partial pressures to describe the composition of gases and Graham's law to predict diffusion of gases.
ACIDS AND BASES
5. Acids, bases, and salts are three classes of compounds that form ions in water solutions. As a basis for understanding this concept:
a. The observable properties of acids, bases, and salt solutions.
b. Acids are hydrogen-ion-donating and bases are hydrogen-ion-accepting substances.
c. Strong acids and bases fully dissociate and weak acids and bases partially dissociate.
d. How to use the pH scale to characterize acid and base solutions.
e. The Arrhenius, Bronsted-Lowry, and Lewis acid-base definitions.
f. How to calculate pH from the hydrogen-ion concentration.
g. Buffers stabilize pH in acid-base reactions.
SOLUTIONS
6. Solutions are homogenous mixtures of two or more substances. As a basis for understanding this concept:
a. The definitions of solute and solvent.
b. How to describe the dissolving process at the molecular level by using the concept of random molecular motion.
c. Temperature, pressure, and surface area affect the dissolving process.
d. How to calculate the concentration of a solute in terms of grams per liter, molarity, molality, parts per million, and percent composition.
e. The relationship between the molality of a solute in a solution and the solution's depressed freezing point or elevated boiling point.