Chem. Final!!

What is acid-base titration?

a laboratory procedure in which a reaction is carried to its equivalence point—the point at which the reactants are in exact stoichiometric proportions; titrations are useful in determining the concentrations of unknown solutions.

Use molecular orbital theory to determine which molecule is diamagnetic.

a) CO b) B2 c) O2 d) none of the above (all are paramagnetic)

Use molecular orbital theory to predict which species has the strongest bond.

a) N2 b) N2 - c) N2 + d) All bonds are equivalent according to molecular orbital theory.

Define ionic equation

a chemical equation showing all of the species as they are actually present in solution.

Define molecular equation

a chemical equation showing the complete, neutral formulas for every compound in a reaction.

What is molarity?

the amount of solute (in moles) divided by the volume of solution (in liters).

percent yield

(actual yield/theoretical yield) * 100%.

What is an acid-base reaction?

An acid base reaction is when an acid and a base are placed together and they react to neutralize the acid and base properties.

What are significant figures?

Non-zero digits are always significant, any zeros between two significant figures, and a final zero or trailing zeros in the decimal portion ONLY are significant.

What is a oxidation-reduction reaction?

Oxidation is a removal of of an electron. A reduction is defined as the addition of an electron to a substance. Electrons transfer from one reactant to the other.

Physical change

The atoms or molecules that compose a substance do not change their identity For example, when water boils, it changes from the liquid state to the gas state, but the molecules composing the water remain intact

Define net ionic equation

The balanced chemical equation without spectator ions. Only the species that actually change during the reaction.

What is enthalpy change?

The heat energy transferred in a reaction at constant pressure

Reaction stoichiometry?

The numerical relationships between chemical amounts in a balanced chemical equation coefficients in a chemical equation specify the relative amounts in moles of each of the substances involved in the reaction.

limiting reactant

The reactant that limits the amount of product in a chemical reaction. makes the least amount of product.

What is molecular orbital theory?

This states that each atom's orbitals are replaced by totally new orbitals when a molecule forms.

Writing and Balancing Equations

Write a skeletal (unbalanced) equation by writing chemical formulas for each of the reactants and products. Balance atoms that occur in more complex substances first. Always balance atoms in compounds before atoms in pure elements. Balance atoms that occur as free elements on either side of the equation last. Always balance free elements by adjusting the coecient on the free element. If the balanced equation contains coecient fractions, clear these by multiplying the entire equation by the denominator of the fraction. Check to make certain the equation is balanced by summing the total number of each type of atom on both sides of the equation.

What is hybridization?

a mathematical procedure in which the standard atomic orbitals are combined to form new atomic orbitals called hybrid orbitals that correspond more closely to the actual distribution of electrons in chemically bonded atom.

What is a aqueous solution?

a solution in which water is the solvent

Classify each property as physical or chemical.

a. the tendency of ethyl alcohol to burn b. the shine of silver c. the odor of paint thinner d. the flammability of propane gas.

A combustion reaction

involves the reaction of a substance with O2 to form one or more oxygencontaining compounds, often including water. reactions also emit heat.

What are the standard SI base units of length, mass, time, and temperature?

meters, kilograms,

Theoretical yield

the amount of product that can be made in a chemical reaction based on the amount of limiting reactant.

Reactant in excess

occurs in a quantity greater than is required to completely react with the limiting reactant.

Chemical change

process by which a fossil fuel such as gasoline burns in the presence of oxygen atoms rearrange and the original substances (in this case gasoline) transform into different substances (in this case water and carbon dioxide). include the rusting of iron, the burning of sugar in a hot pan, and the transformation of oxygen and carbon dioxide into glucose that occurs within plants during photosynthesis.