AP Chemistry Exam Review

Flashcards to help review key concepts for the AP Chemistry Exam.

Noble gases

Are the most difficult to oxidize in a given period of the periodic table

Actinides

Are always radioactive

Halogens

Are the most likely to form anions

NH3 (g)

Has molecules with a pyramidal shape.

HBr (g)

Is a strong electrolyte in aqueous solution

HBr (g)

Is the slowest to effuse through a small opening at 25°C and 1 atm

Entropy

Quantity would be zero for a pure, perfect crystal at 0 K.

Activation energy

Quantity typically determined by measuring the rate of a reaction at two or more different temperatures

ΔH < 0, ΔS > 0

Must be true for a reaction that is spontaneous at all temperatures

ΔH > 0, ΔS > 0

True for the evaporation of water at 25°C and 1 atm

ΔH < 0, ΔS > 0

True for the combustion of liquid pentane, C5H12(l), to form H2O(g) and CO2(g) at 1 atm

Pb2+(aq) + CrO42–(aq) → PbCrO4(s)

A precipitation reaction

Ag+(aq) + 2 NH3(aq) → [Ag(NH3)2]+(aq)

A Lewis acid-base reaction that produces a coordination complex

2 Mg(s) + O2(g) → 2 MgO(s)

An oxidation-reduction reaction that is also a synthesis reaction

London (dispersion) forces

Forces between neighboring CH4 molecules are best characterized as

CO2

A molecule that is nonpolar but contains polar bonds

Protons: 55, Neutrons: 79, Electrons: 55

Shows the correct number of protons, neutrons, and electrons in a neutral cesium-134 atom.

C2H6

Molecules contains only single bonds.

Si

A solid formed by elements combining with oxygen, creating a covalent network.

ZnF2

The precipitate must be

Br2

An element expected to have the highest melting point on the basis of strength of intermolecular forces

The vapor pressure of the liquid becomes equal to the atmospheric pressure on the surface of the liquid

The temperature at which a pure liquid in an open vessel boils.

C12 is a stronger oxidizing agent than I2.

Accounts for the fact that a galvanic cell based on the reaction represented by C12(g) + 2 I(aq) → 2 C1(aq) + I2(aq) will generate electricity

t4

The time the sample contains the most liquid, as the sample goes through phase changes starting as a gas, and heat is removed at a constant rate.

There is a sufficient volume of water to absorb the heat released

When diluting concentrated H2SO4, one should slowly add acid to a beaker of water rather than add water to a beaker of acid. This precaution ensures that

NH3

The conjugate acid of NH2 –

Phosphate

Salts containing these ions are generally insoluble in cold water

10

The number of electrons transferred in the reaction represented by the balanced equation above.

Temperature: 800K, Pressure: 0.1 atm

Conditions of temperature and pressure would 1.0 mol of the real gas CO2(g) behave most like an ideal gas

H2

The London (dispersion) forces are weakest for

sp

The hybridization of the carbon atoms in a molecule of ethyne, represented by H—C≡C—H

0 < K < 1

This must be true about the value of the equilibrium constant for the reaction at this temperature: 2 NO2(g) N2O4(g)

Ni2+ forms a complex ion with NH3.

Best explains why, when aqueous NH3 is first added to a solution containing Ni2+, a precipitate forms, but when an excess of aqueous NH3 is added, the precipitate dissolves.

25 mL pipet

The pieces of laboratory glassware that should be used to most accurately measure out a 25.00 mL sample of a solution

F– has a larger nuclear charge than O2– has.

Best helps to account for the fact that the F– ion is smaller than the O2– ion.

0.10 M NaF

Solutions has a pH greater than 7.0

Move the tube downward until the water level is the same inside and outside the tube.

The step, if any must be taken to make it possible to determine the total gas pressure inside the tube, in a laboratory experiment where H2(g) is collected over water in a gas-collection tube.

Frequency of collisions of reactant particles, Kinetic energy of collisions of reactant particles, and Orientation of reactant particles during collisions

Factors that affect the rate of a chemical reaction

4

When the equation …H+(aq) + …NO2 –(aq) + …Cr2O7 2–(aq) → …Cr3+ (aq) +…. NO3 –(aq) +… H2O(l) is balanced and all coefficients are reduced to lowest whole-number terms, the coefficient for H2O(l) is

average molecular kinetic energy

At standard temperature and pressure, a 0.50 mol sample of H2 gas and a separate 1.0 mol sample of O2 gas have the same

chlorine

Naturally produced amino acids typically contain all of the following elements EXCEPT

O – F

Of the following single bonds, which is the LEAST polar?

NH4C1(aq) + HC1(aq)

When mixed, each of the following pairs of reactants gives visible evidence of a chemical reaction EXCEPT

The same in both containers because the temperature is the same

The figure above shows two closed containers. Each contains the same volume of acetone in equilibrium with its vapor at the same temperature. The vapor pressure of the acetone is

O3

A molecule has an angular (bent) geometry that is commonly represented as a resonance hybrid of two or more electron-dot structures