AP CHEMISTRY

GASES

100

Using gas laws, by how much will the pressure in a rigid container increase or decrease if the temperature is doubled?

Increase by a factor of 2.

200

Which elemental gas behaves most like an ideal gas?

Helium

300

Rank the gases in order of least to greatest average molecular speed: H₂, He, N₂, O₂, H₂O (at same temperature)

O₂, N₂, H₂O, He, H₂

400

7.0 mol CO₂, 7.0 mol Ar, 7.0 mol N₂, and 4.0 mol Ne are trapped in a rigid container with a total pressure of 10.0 atm. What is the partial pressure exerted by neon?

1.6 atm

500

A 5.0 L vessel contains 2.0 moles of helium and 3.0 moles of hydrogen at a pressure of 10 atm. Maintaining a constant temperature, an additional 3.0 moles of hydrogen are added. What is the new partial pressure of hydrogen in the vessel?

12.0 atm. The initial partial pressure of the hydrogen is 10 atm * (3.0/5.0) = 6.0 atm. The amount of hydrogen present is doubled from 3.0 to 6.0 moles, so the partial pressure will increase proportionally to 12.0 atm.

Chemical Bonding and VSEPR Theory

100

The compound most likely to be ionic: KF CCl4 CO2 ICl CS2

What is KF? Bonds formed from elements with greater differences in electronegativity are most likely ionic in nature.

200

In which this bond does the oxygen atom posses a partial positive charge: O-H, O-F, N-O, O-C, or P-O?

O-F. Since fluorine is the most electronegative element in the Periodic Table, the oxygen atom, when covalently bonded to the fluorine atom, will have a partial positive charge.

300

CH₃CH₂OH and CH₃OCH₃ have the same formulas but different boiling points. Based on their structure and IMFs, which one will have higher boiling point and why?

CH₃CH₂OH, because it can form hydrogen bonds due to its hydroxyl group.

400

The molecule geometry of PH3 according to the VSEPR theory.

What is Trigonal Pyramidal?

500

This is the ELECTRON geometry around the central atom in the molecule IF₅.

What is octahedral?

Thermo-Chemistry

100

This is the driving force for a spontaneous process which readily occurs without intervention. Which measures molecular randomness or disorder.

What is entropy?

200

Heat is exchanged in this direction when urea (the system) is dissolved endothermically in water (the surroundings)

What is from surroundings to the system?

300

This is the equation for the specific heat of a substance

What is C = q/(m*dT)?

400

This is the energy absorbed when 10g of liquid water goes from 289K to 299K

What is 418 J

500

This law states that enthalpy change, in going from a particular set of reactants to a particular set of products, is the same whether the reaction takes place in one step or in a series of steps. Enthalpy is a state function.

What is Hess's Law?

Acids AndBases

100

This type of molecule gives up a proton easily and yields a weak conjugate base when reacting with water

What is a strong acid

200

The pH of a solution where [OH-] is 1.0x10^-5M

What is pH = 9.0?

300

What is the equation for calculating pH when only given [OH-]?

What is pH = 14 + log([OH-])

400

HA is a weak acid which is 4.0% dissociated at .100M. This is the Ka for this acid.

What is 0.00017 (will also accept .00016)

500

The pH of 1M of an acid with Ka = 4 x 10^-6

What is pH = 2.7?

AP MIX

100

The property of elements that explains why the atomic mass for iron given in the Periodic Table is 55.845 rather than 55, 56, or 57

What are Isotopes?

200

1s²2s²2p⁶ is the electron configuration for which group 2 ion?

What is magnesium?

300

The concentration of IONS in 1.2 M aluminum nitrate solution.

What is 4.8M? Al(NO₃)₃ contains four ions per formula unit each mole of Al(NO3)3 contributes four moles of ions 1.2mol/L*4=4.8 mol of ions/L

400

This is the equilibrium expression for the acid HA

What is Ka = ([H₃O+][A-])/([HA])?

500

In the molecule CH₄ what this the measurement of the C--H bond angle?

109.5