Log in
Chemistry
1
answer
0
watching
688
views
13 Dec 2019

2.There are four equal-sized bowls with equal amounts of milk.

Bowl A is covered, and the milk is at room temperature.
Bowl B is uncovered, and the milk is warmer than room temperature.
Bowl C is uncovered, and the milk is cooler than room temperature.
Bowl D is uncovered, and the milk is at room temperature.

Which bowl has the highest vapor pressure?

A.bowl A

B.bowl B

C.bowl C

D.bowl D

3.Cup A and cup B are identical. They contain equal volumes of soup at equal temperatures. Both cups are put in a refrigerator. Cup A has a lid, but cup B does not. Which statement best explains why cup A will cool more slowly than cup B?

A.Water vapor won’t be able to escape from cup A.

B.The most energetic water molecules from cup A will escape more rapidly.

C.No molecules will be able to evaporate at the surface of cup B.

D.No molecules will be able to evaporate at the surface of cup A.

4. Based on the enthalpy changes given for the reactions, which reactions are endothermic? CHOOSE ALL THAT APPLY

2H2O → 2H2 + O2, ΔH = 484 kJ

C + O2 → CO2, ΔH = -394 kJ

H2 + Br2 → 2HBr, ΔH = -73 kJ

2NH3 → N2 + 3H2, ΔH = 92 kJ

Watch
1
answer
0
watching
688
views

For unlimited access to Homework Help, a Homework+ subscription is required.

Reid Wolff
Reid WolffLv2
17 Dec 2019

Unlock all answers

Get 1 free homework help answer.
Already have an account? Log in
Share
discord banner image
Join us on Discord
Chemistry Study Group
Join now

Related textbook solutions

Basic Chemistry
5 Edition,
Timberlake
ISBN: 9780134138046
Principles of Chemistry Molecular Approach
4th Edition,
Tro
ISBN: 9780134112831
Chemistry: Structure and Properties
2nd Edition,
Tro
ISBN: 9780134293936
Principles of Chemistry Molecular Approach
3rd Edition, 2014
Tro
ISBN: 9780321971944
Chemistry: A Molecular Approach
3rd Edition,
Tro
ISBN: 9780321809247
Chemistry: A Molecular Approach
5th Edition,
Tro
ISBN: 9780134874371
Principles of Chemistry: A Molecular Approach
4th Edition,
Tro
ISBN: 9780134895741
Chemistry: The Central Science
14th Edition, 2017
Brown
ISBN: 9780134414232

Related questions

At what temperature is the equilibrium vapor pressure of water about 400 torr?
Choose one answer.
a. 30oC
b. 45oC
c. 60oC
d. 80oC

Which of the following statements are true about evaporation for a liquid?

Help: Evaporation

Choose at least one answer.
a. Only the most energetic molecules evaporate.
b. This means the average kinetic energy of the remaining molecules decrease.
c. This has no effect on the average kinetic energy of the remaining molecules.
d. Consequently, the temperature of the remaining liquid drops, that is, evaporation is a cooling process.
e. Consequently, the temperature of the remaining liquid stays the same.
All but one of the following statement is true. Using your everyday experience, check the false one.
Choose one answer.
a. Evaporation takes place from the surface of water.
b. A cup of soup in a bowl cools more slowly than a cup of soup on a large plate.
c. Hot water evaporates from a pan faster than cool water.
d. Water evaporates as a gas or vapor.
e. The vapor pressure of room temperature water in a sealed glass continues to rise until the glass breaks.
f. The vapor pressure of room temperature water in a sealed glass reaches an equilibrium vapor pressure, that is, the evaporation rate of water equals its condensation rate from the gas phase.

28. Which of the following is broken when water evaporates?

A. Nonpolar covalent bonds

B. Ionic Bonds

C. Hydrogen Bonds

D. Polar Covalent Bonds

 

29. You are asked to indicate the type and number of atoms in molecules. Which representation would work?

A. Molecular formula

B. Structural formula

C. Ball and stick model

D. Space fitting model

 

30. Which of the following correctly describes chemical equilibrium?

A. Forward and reverse reactions continue with no net effect on the concentrations of the reactants and the products.

B. Concentrations of products are higher than the concentration of the reactants.

C. There are equal concentrations of products and reactants while forward and reverse reactions continue.

D. There are equal concentrations of reactants and products, and the reactions have stopped.

 

31. To act as an effective coolant in a car's radiator, a substance has to have the capacity to absorb a great deal of heat. You have a reference with tables listing the physical properties of many liquids. In choosing a coolant for your car, which table would you check first?

A. pH

B. Density at room temperature

C. Heat of vaporization

D. Specific heat

 

32. Water has many exceptional and useful properties. Which is the rarest property among compounds?

A. Water is a solvent

B. Solid water is less dense than liquid water

C. Water has high heat capacity

D. Water has surface tension


For which system below would quantum effects be leastnoticeable?


-The collision of two N2 molecules in a gas, whichchanges the rotational energy of both

-Polarization of the electron density of ethanol resulting inexcitation of vibrational motions

-An electron-sized particle moving in a 1 m3 box asthe temperature decreases by 10 degrees

-A hydrogen atom being struck by a UV photon






We have dealt with two different ensembles, canonical andmicrocanonical. Which of the following statements is inaccurateregarding these ensembles?


-The canonical ensemble is always considered as a subset of alarger reservoir, which acts as the surroundings.

-The microcanonical ensemble is defined to have constant energy,volume, and composition.

-The microcanonical ensemble is a smaller subset of microstatesof the canonical ensemble.

-The canonical ensemble is generally more useful than themicrocanonical for chemical processes.





Which statement below is most correct regarding the partitionfunction of an ensemble?

-For a given temperature, the high-energy contributions to thepartition function are more heavily weighted.

-Once a partition function is defined in a specific ensemble, itis valid in all other ensembles.

-It tells us the numerical order of the energy levels for agiven system.

-It provides a measure of the energy levels available to asystem at a given temperature.






Consider a cup-carrier from your favorite take-out restaurant.The carrier can hold four cups, and you have to place two cups (onelarge, one small) into the carrier, with no preference forposition. How many microstates can you form with two cups in thefour spaces?


-12

-8

-16

-6






Boltzmann's definition of the entropy was a breakthrough inunderstanding statistical thermodynamics. What is the bestdefinition of Boltzmann's entropy?


-The Boltzmann entropy is a count of the total distinctmicrostates in a system.

-The Boltzmann entropy is a measure of the randomness of anensemble.

-The Boltzmann entropy is a count of the accessible energylevels at a given temperature.

-The Boltzmann entropy is a measure of the useful work availablein an ensemble.






Our canonical ensemble was defined such that the temperature,volume, and number of particles were each held constant. In termsof the Legendre transform, which thermodynamic potential isfundamental in the canonical ensemble?


-The Helmholtz energy

-The internal energy

-The Gibbs energy

-The enthalpy






The equipartition principle can be used to estimate the constantvolume heat capacities of gases. Under which circumstances wouldthe full equipartition heat capacity most closelyapproximate the measured value of CV?


-A sample of N2 gas at 373K

-A sample of propane gas (C3H8) at roomtemperature

-A sample of water vapor at 373K

-A sample of Br2 vapor at room temperature






Which factor below does not contribute to the rotationalpartition function of a molecule?



-The rotational quantum number

-The nuclear and electronic spin states

-The rotational constant(s)

-The temperature of the molecule






We were able to reduce the vibrational partition function froman infinite series to a function of a single exponential, but onlyapproximately. Which approximation below was NOT used?


-We assumed that the vibrational energy can be expressed asv?e.

-We assumed that the energy levels were close enough to allowintegration instead of summation.

-We assumed that the vibrational motion is purely harmonic.

-We assumed that the separations are relatively small, due tohigh temperature or lower vibrational constant.






The derived partition function for an ideal gas depends on allof the physical parameters listed below except for which one?


-Molecular symmetry

-The temperature of the molecules

-The volume of the sample

-Mass of the molecules






Deriving the translational partition function is more involvedthan deriving the rotational and vibrational partition functions.Which statement below is NOT a reason for this?


-There are so many possible translational energy levels, thatthe integral does not converge to a finite value.

-The integral of translational states for a single particle mustbe taken over a 6-dimensional hypervolume.

-The degeneracy of translational states is not obvious becausethey lie so close in energy.

-Translational degrees of freedom involve interactions betweenall molecules in the sample, whereas rotations and vibrations donot.






The connection between the Equipartition Principle and thetranslational partition functions helped to demonstrate that thetemperature of a system depends on the easily excited degrees offreedom. Why should this be true?


-In systems with easily excited degrees of freedom, a change inthe entropy requires energy changes on the order of thermalenergy.

-In systems with easily excited degrees of freedom, smallincreases in the pressure make excited states more accessible,

increasing the temperature.

-In systems with easily excited degrees of freedom, thepotential energy is no longer dependent on the temperature of thesystem.

-In systems with easily excited degrees of freedom, thermalenergy is sufficient to allow one to treat the energy levels as acontinuum.





The connection between the Maxwell-Boltzmann distribution andthe translational partition function allowed us to betterunderstand the distribution of speeds. Which statement below is NOTa consequence of the translational partition function?


-The population of the lowest speeds is very small.

-The pressure of the gas increases as the velocityincreases.

-An increase in the temperature will result in shifting thedistribution to higher energies.

-The population of the highest speeds is very small.





When dealing with quantum energy levels, there are severalimportant factors to consider. Which concept below is NOT importantto quantum energy levels?


-The set of quantum numbers

-Degeneracy

-The deBroglie wavelength

-The ground state






Weekly leaderboard

Home
Homework Help 3,900,000
Chemistry 830,000
Start filling in the gaps now
Log in