Ensigns Chemistry 1210 Final

How many orbitals are present in the (i) n = 1 and (ii) n = 3 shells?

(i) = 1 and (ii) = 9

Referring to the previous problem, what is the mol fraction of He in this gas mixture? a.0.333

0.799

What is the most electronegative element?

F

Draw lewis structure for the azide ion, N3-. The bonding in the N3- is best described by how many TOTAL bonds, and of which types?

two sigma bandstand two pi bonds

You have a separatory funnel containing water and carbon tetrachloride, which are immiscible. Predict which phases the following compounds would dissolve in within the separatory funnel (i) I2 (ii) C6H14 (iii) CuSO4 (iv) NH3 Water phase CCl4 phase (a) CuSO4, NH3, I2, C6H14, (b) CuSO4, NH3, I2 C6H14, (c) CuSO4, NH3, C6H14 I2 (d) I2, C6H14, NH3 CuSO4 (e) I2, C6H14, CuSO4, NH3,

(a) CuSO4, NH3, I2, C6H14,

Which one of the following compounds will have the lowest boiling point? (a) CBr4 (b) CF4 (c) CI4 (d) CCl4

(b) CF4

Calculate the vapor pressure in a sealed flask containing 30.0 g of glucose, C6H12O6, dissolved in 100.0 g of water at 25.0°C. The vapor pressure of pure water at 25.0°C is 23.8 torr. (a) 79.3 torr (b) 7.14 torr (c) 0.693 torr (d) 23.1 torr (e) 24.5 torr

(d) 23.1 torr

During the solution process, disruption of solute-solute interactions _____(i)_______, disruption of solvent-solvent interactions ______(ii)_____, and formation of solute-solvent interactions _____(iii)______. (i) (ii) (iii) (a) releases energy releases energy requires energy (b) requires energy releases energy requires energy (c) releases energy requires energy releases energy (d) requires energy requires energy releases energy (e) requires energy releases energy releases energy

(d) requires energy requires energy releases energy

SeF2 is _________ and CS2 is _________

(i) = polar (ii) = nonpolar

Of the following processes, which are endothermic? (i) sublimation (ii) freezing (iii) condensation (iv) melting (v) deposition (vi) vaporization

(i), (iv), and (vi)

What is the oxidation number on S in the sulfite ion?

+4

Given the following data, determine delta H for the conversion of one mole of H2O(l) to one mole H2O(g) 2H2(g) + O2(g) --> 2H2O(l) delta H = -571.6 kJ 2H2(g) + O2(g) --> 2H2O(g) deltat H = -483.6 kJ

+44.0 kJ

Using the information in the table of average bond energies on page 1, estimate delta H (in kJ) for the combustion of ethanol (be careful to use the right bond energy values and numbers of bonds): CH3CH2OH + 3O2 --> 3H2O + 2CO2

-1255 kJ

Helium balloons are used as instruments for weather forecasting. You have a weather balloon with a volume of 5.00 x 103 liters which is launched when the temperature is 22.5°C and atmospheric pressure is 684 torr. At its final altitude, the atmospheric pressure is 55.0 torr and the volume of the balloon has expanded to 4.50 x 104 liters. What is the temperature at this altitude in degrees celsius?

-59.2 °C

Nitrogen and hydrogen gases combine to form ammonia as shown in the following balanced chemical equation: 3H2(g) + N2(g_ ---> 2NH3(g) deltaH = _______ kJ/mol reaction Under standard conditions and constant pressure the reaction of 10.0 got H2 with excess N2 produces 153 kJ of heat. Use this information to determine the enthalpy change that should be reported for the reaction.

-92.4 kJ

What volume of 6.00 M NaOH would be required to prepare 2.00L of 0.250 M NaOH?

0.0833 L

If you dissolve 0.30 moles of ammonium nitrate in 0.70 liters of solution, what is the total concentration, in moles/liter, of all the ions present in solution?

0.86 M ions

Which of the following solutions will have the lowest freezing point? a. 2.0 M glucose (C6H12O6) b. 1.5 M NaCl c. 1.25 M CaCl2 d. 1.00 M AlCl3 e. 3.0 M NH3

1.00 M AlCl3

1.00 g/cm3 equals how many kg/m3?

1.00 x 10^3

It takes about 200 kJ of energy to bring a cup of water from room temperature to boiling. How many photons of microwave radiation from microwave over with wavelength = 0.12 m would be necessary to provide this 200. kJ of energy?

1.21 x 10 ^29 photons

You have a piece of gold with a mass of 483.0 grams. You have a graduated cylinder containing 50.0 mL of water. you add the piece of gold tot he graduated cylinder, it sinks to the bottom and the water level rises to read 75.0 mL what is the density of gold?

19.3 g/cm^3 d = m/V ml = cm^3

Autoclaves use pressurized steam (gaseous water) to obtain temperatures capable of killing microorganisms. The temperature required to kill microorganisms is 121° Celsius. Assuming water vapor (steam) behaves like an ideal gas, determine the pressure required for an autoclave with a volume of 50.0 liters and containing 3.10 moles of steam to reach 121° Celsius.

2.01 atm.

Given the following information: specific heat of solid water (ice) = 2.09 J/(g•°C), specific heat of liquid water = 4.18 J/(g•°C), specific heat of water vapor = 1.84 J/(g•°C), enthalpy of fusion of water is 6.00 kJ/mol, enthalpy of vaporization of water is 40.67 kJ/mol. You take several ice cubes with a combined mass of 50.0 grams out of your freezer where they are at a temperature of -15 °C and let them melt until they reach room temperature, which is 25 °C. What was the heat change associated with this process?

23.4 kJ

For the combustion of the hydrocarbon octane (C8H18) in air, what is the coefficient in front of 02 when the chemical equation for the reaction is properly balanced?

25

A simple way to prepare oxygen in the laboratory is by the decomposition of potassium chlorate, which occurs upon heating: 2KClO3(s) 3O2(g) + 2KCl(s) Assuming the reaction goes to completion, if 10.0 grams of KClO3 are decomposed according to the balanced chemical equations shown above, what volume of O2 will be produced at a pressure of 1.00 atmosphere and a temperature of 25.0° C?

3.00 liters

90Sr2+ has how many protons, neutrons and electrons?

38 protons, 52 neutrons, and 36 electrons

You have a 5.00 liter vessel that contains 2.00 g CO2, 3.00 g He, and 4.00 g N2 at 42° C. What is the total pressure in the vessel in atmospheres?

4.85 atm.

Match the arrows with the correct phase equilibria: solid-liquid liquid-gas solid-gas (a) (ii) (iii) (i) (b) (i) (iii) (ii) (c) (i) (ii) (iii) (d) (iii) (ii) (i) (e) (ii) (i) (iii)

A

Examine the heating curve at the right. Which letters correspond to heating the liquid?

C

Butyric acid s responsible for the rancid odor you smell when certain foods decompose. Butyric acid is composed of 54.4% C, 9.152% H, and 36.32% O by mass. what is the empirical formula for butyric acid?

C2H4O

Which set of conditions will always cause the volume of a defined amount of gas to decrease? a. increasing pressure and increasing temperature b. decreasing pressure and increasing temperature c. decreasing pressure and decreasing temperature d. increasing pressure and decreasing temperature e. more than one of the above will always result in an increased volume

D. increasing pressure and decreasing temperature

Of the following which are exothermic processes?

Deposition and Condensation

if 4.0 moles of FE and 6.0 moles of O2 are used in the reaction 4Fe + 3O2 --> 2Fe2O3, then the limiting reactant is ___________ and the theoretical yield of Fe2O3 is ________mol.

Fe, 2.0 mol Fe2O3

What is fusion?

Fusion is melting

The fact that H2Se has a slightly higher boiling point than H2S i due to?

Greater London-Dispersion forces in H2Se.

What is needed for hydrogen bonding?

Has to be bonded to N, O, or F

Which of the following statements correctly states a consequence of the first law of thermodynamics?

In a chemical reaction, energy that is gained by the surroundings must equal the energy lost by the system.

What is the delta-h of fusion

Latent heat change from solid to liquid.

Sea of electrons

Metallic bonding

The following statement best describes what type of molecular interaction: "ionization of atoms to form cations, which are electrostatically attracted to a mobile sea of electrons.

Metallic bonding

Which is the correct balanced net ionic equation for the reaction of the insoluble metal hydroxide "mile of magnesia", Mg(OH)2, with hydrochloric acid in your stomach?

Mg(OH)2(s) + 2H+(aq) --> 2H2O(l) + Mg2+ (aq)

Why does ice have a reverse slope on the chart?

Molecules slow down forming more Hydrogen Bonds and spreading out.

Which of the following do you predict to be the least polar covalent bond?

N-O

During the solution process which process(es) are exothermic?

Only formation of solute-solvent interactions.

The ability or tendency of an atoms or molecules electron cloud to be distorted from its normal shape is referred to as?

Polarizability

For which of the following is the molecular geometry see saw?

SF4

In a phase diagram, the point where all three lines intersect represents?

The conditions of pressure and temperature where the solid, liquid, and gas can all exist at equilibrium simultaneously

A chemical reaction has delta E = +10.0 kJ/mol. This reaction is conducted under conditions where both heat and work occur. The heat change in the reaction is -30.0 kJ/mol. which statement is correct about the amount of work involved in this transformation?

The surrounding perform 40.0 kJ of work on the system during this transformation.

Which is the best definition of boiling point?

The temperature where the vapor pressure of a liquid becomes equal to the external pressure.

Which of the following possible lewis structures for the cyanate ion (CNO-) is bot a correct structure AND the best structure based on formal charge considerations

Tripple bond with N and single bond with O

Where three lines intersect on phase diagram?

Tripple point

Which of the following is an incorrectly stated relationship between two variables for an ideal gas?

V ∝ 1 n

Enthalpy is the heat of a reaction under what conditions? a. (b) constant pressure b. (a) constant volume c. (c) constant temperature d. both (a) and (b) e. all of the above

a. (b) constant pressure

H2Se is ____(i)____ and SO3 is ______(ii)________. a. (i) polar; (ii) nonpolar b. (i) nonpolar; (ii) polar c. (i) polar; (ii) polar d. (i) nonpolar; (ii) nonpolar

a. (i) polar; (ii) nonpolar

For formaldehyde, CH2O, where C is the central atom, the hybridization on C is ____(i)_______ and the hybridization on O is _____(ii)________. a. (i) sp2; (ii) sp2 b. (i) sp2; (ii) sp3 c. (i) sp3; (ii) sp3 d. (i) sp2; (ii) sp e. (i) sp; (ii) sp2

a. (i) sp2; (ii) sp2

For COS, where C is the central atom, the hybridization on C is ____(i)_______ and the hybridization on S is _____(ii)________. a. (i) sp; (ii) sp2 b. (i) sp2; (ii) sp3 c. (i) sp3; (ii) sp3 d. (i) sp2; (ii) sp e. (i) sp2; (ii) sp2

a. (i) sp; (ii) sp2

Order the following aqueous solutions from highest to lowest boiling point: (i) 1.0 M glucose (C6H12O6) (ii) 2.0 M NaCl (iii) 1.25 M CaCl2 (iv) 0.5 M Al2(SO4)3 a. (ii) > (iii) > (iv) > (i) b. (iv) > (i) > (iii) > (ii) c. (ii) > (iii) > (i) > (iv) d. (i) > (iii) > (iv) > (ii) e. (i) > (iv) > (iii) > (ii)

a. (ii) > (iii) > (iv) > (i)

Which of the following molecules cannot use dipole-dipole attractions as an intermolecular attractive force? (i) AsCl3 (ii) SeF4 (iii) H2Se (iv) SO3 a. (iv) only b. (ii) and (iv) c. (ii) and (iii) d. (i) and (iii) e. (ii), (iii), and (iv)

a. (iv) only

Which of the following molecules cannot use dipole-dipole attractions as an intermolecular attractive force? (i) AsI3 (ii) SF4 (iii) H2Se (iv) BF3 a. (iv) only b. (ii) and (iv) c. (ii) and (iii) d. (i) and (iii) e. (ii), (iii), and (iv)

a. (iv) only

What is the oxidation number on the S atom in sulfurous acid, H2SO3? a. +4 b. +6 c. +8 d. 0 e. -4

a. +4

Ammonia is synthesized by the combination of hydrogen and nitrogen according to the following chemical reaction: 3H2(g) + N2(g) → 2NH3(g) ΔH° = -92.4 kJ/mol reaction What will be the energy change associated with forming 25.0 moles of NH3? a. -1.15 x 103 kJ b. -3.69 kJ c. -111 kJ d. -7.70 x 102 kJ e. -2.31 x 103 kJ

a. -1.15 x 103 kJ

Using the information in the table of average bond energies on Page 1 of this exam, estimate ΔH (in kJ/mol reaction) for the combustion of BUTANE (be careful to use the right bond energy values and numbers of bonds, and look carefully at the reaction stoichiometry!): a. -5261 kJ b. -5000 kJ c. -10,435 kJ d. +587 kJ e. -11,696 kJ

a. -5261 kJ

The Henry's constant for O2 is 1.3 x 10-3 M/atm at 25°C, and the mol fraction of O2 in air is 0.21. You are at a certain altitude, either above or below sea level (in a coal mine or on a mountain) where the concentration of dissolved oxygen in water is 1.7 x 10-4 M. What is the total atmospheric pressure at your altitude? a. 0.62 atm b. 1.6 atm c. 0.13 atm d. 7.6 atm e. 0.027 atm

a. 0.62 atm

1.00 mg/cm3 equals ______ μg/m3. a. 1.00 x 109 b. 1.00 x 1012 c. 1.00 x 107 d. 1.00 x 106 e. 1.00 x 10-3

a. 1.00 x 109

1.00 mg / cm2 equals ______ kg / m2. a. 1.00 x 10^-2 b. 1.00 x 10^2 c. 1.00 x 10^-6 d. 1.00 x 10^4 e. 1.00 x 10^-4

a. 1.00 x 10^-2

Given the following information: specific heat of solid water (ice) = 2.09 J/(g•°C), specific heat of liquid water = 4.18 J/(g•°C), specific heat of water vapor = 1.84 J/(g•°C), enthalpy of fusion of water is 6.00 kJ/mol, enthalpy of vaporization of water is 40.67 kJ/mol What is the heat change associated with the following cooling process: 75.0 grams of steam originally at 155 degrees Celsius is allowed to cool to liquid water at 90.0 degrees Celsius. a. 1.80 x 102 kJ b. 219 kJ c. 1.09 x 104 kJ d. 35.7 kJ e. 74.6 kJ

a. 1.80 x 102 kJ

How many hydrogen atoms are present in 50. grams of sucrose, C12H22O11? a. 1.9 x 10^24 b. 8.8 x 10^22 c. 4.0 x 10^21 d. 9.1 x 10^25 e. 2.3 x 10^29

a. 1.9 x 10^24

How much energy is required to excite an electron in a hydrogen atom from n = 3 to n = 7? a. 1.98 x 10-19 J b. 4.15 x 10-19 J c. 8.72 x 10-19 J d. 4.45 x 10-20 J e. 3.11 x 10-19 J

a. 1.98 x 10-19 J

How much energy is required to excite an electron in a hydrogen atom from n = 3 to n = 7? a. 1.98 x 10^-19 J b. 4.15 x 10^-19 J c. 8.72 x 10^-19 J d. 4.45 x 10^-20 J e. 3.11 x 10^-19 J

a. 1.98 x 10^-19 J

How much energy is released when an electron in the hydrogen atom in n = 9 falls down to n = 3? a. 2.15 x 10^-19 J b. 4.84 x 10^-19 J c. 1.31 x 10^-17 J d. 1.57 x 10^-16 J e. 3.93 x 10^-20 J

a. 2.15 x 10^-19 J

The decomposition of hydrogen peroxide in water occurs as shown in the balanced chemical equation below: 2H2O2(aq) → 2H2O(l) + O2(g) This reaction occurs very rapidly in the presence of a suitable catalyst. What mass of H2O2 would produce 5.25 liters of oxygen gas at a pressure of 1.75 atmospheres and a temperature of 37.0°C? a. 24.6 g H2O2 b. 6.14 g H2O2 c. 206 g H2O2 d. 13.0 g H2O2 e. 3.25 g H2O2

a. 24.6 g H2O2

Sodium metal react with water to form sodium hydroxide and hydrogen gas. What is the net ionic equation for this reaction? a. 2Na(s) + 2H2O(l) → 2Na+(aq) + 2OH- (aq) + H2(g) b. 2Na(s) + 2H2O(l) → 2NaOH (aq) + H2(g) c. 2H2O(l) → 2OH- (aq) + H2(g) d. 2Na(s) + 2H2O(l) → 2OH- (aq) + H2(g) e. 2H2O(l) → 2OH- (aq) + H2(g) + 2Na+(aq)

a. 2Na(s) + 2H2O(l) → 2Na+(aq) + 2OH- (aq) + H2(g)

Given the following data: specific heat of solid water (ice) = 2.09 J/(g•°C), specific heat of liquid water = 4.18 J/(g•°C) specific heat of water vapor = 1.84 J/(g•°C), enthalpy of fusion (melting) of water is 6.00 kJ/mol, enthalpy of vaporization of water is 40.67 kJ/mol What will be the energy change associated with converting 125 grams of liquid water at 20.00 °C to steam at 121.00 °C? a. 329 kJ b.352 kJ c. 297 kJ d. 320 kJ e. 88.3 kJ

a. 329 kJ

What is the dissolved concentration of O2 in a lake at a depth of 33 feet where the pressure is 2.00 atm and the temperature is 20 degrees Celsius? The Henry's law constant for O2 is 1.30 x 10-3 M/atm and the mol fraction of O2 in air is 0.21. a. 5.5 x 10-4 M b. 2.7 x 10-4 M c. 1.2 x 10-2 M d. 3.1 x 10-3 M e. 6.2 x 10-3 M

a. 5.5 x 10-4 M

The binary compound (HnX) of which of the following atoms would you predict has the highest vapor pressure at a given temperature? a. C b. Si c. O d. S e. Se

a. C

Propylene glycol is an important industrial commodity with a wide range of uses. It is composed of 47.35% C, 10.60% H, and 42.05% O by mass. What is the empirical formula for propylene glycol? a. C3H8O2 b. C4H12O3 c. C4H10O4 d. CH4O e. CH2O

a. C3H8O2

What are the spectator ion(s) for the reaction of the insoluble salt "milk of magnesia", Mg(OH)2, with hydrochloric acid in your stomach. a. Cl- only b. Mg2+ and Clc. Mg2+ only d. H+ and OHe. H+ and Cl-

a. Cl- only

For a collection of molecules or ions of relatively constant size, rank the following intermolecular attractive forces from WEAKEST (1st) to STRONGEST (last) a. London dispersion, dipole-dipole, hydrogen bond , ion-dipole b. London dispersion, dipole-dipole, ion-dipole, hydrogen bond c. dipole-dipole, London dispersion, ion-dipole, hydrogen bond d. dipole-dipole, London dispersion, hydrogen bond, ion-dipole e. dipole-dipole, ion-dipole, hydrogen bond, London dispersion

a. London dispersion, dipole-dipole, hydrogen bond , ion-dipole

Which of the following atoms is most likely to violate the general trend observed for electron affinity when moving from left to right within row 3 of the periodic table? a. Mg and P b. Mg and S c. Al and S d. Al and P e. P and S 44. How many equivalent resonance

a. Mg and P

Which is the correct balanced complete ionic equation for the reaction of the insoluble metal hydroxide "milk of magnesia", Mg(OH)2, with hydrochloric acid in your stomach. a. Mg(OH)2(s) + 2 H+ (aq) + 2 Cl- (aq) 2 H2O(l) + Mg2+ (aq) + 2Cl- (aq) b. Mg(OH)2(s) + 2 HCl(aq) 2 H2O(l) + MgCl2(aq) c. Mg2+ (aq) + 2 OH- (aq) + 2 H+ (aq) + 2 Cl- (aq) 2 H2O(l) + Mg2+ + 2Cl- (aq) d. Mg(OH)2(s) + 2H+ (aq) 2 H2O(l) + Mg2+ (aq) e. 2 OH- (aq) + 2 H+ (aq) 2 H2O(l)

a. Mg(OH)2(s) + 2 H+ (aq) + 2 Cl- (aq) 2 H2O(l) + Mg2+ (aq) + 2Cl- (aq)

When ammonium acetate dissolves in water, the temperature decreases. Which of the following statements (a) to (d) about this solution process is NOT correct? a. energy is released when solute-solute interactions are disrupted b. solution formation is endothermic c. energy is released when solute-solvent interactions are formed d. energy is required to break solvent-solvent interactions e. all of the statements (a) to (d) are correct

a. energy is released when solute-solute interactions are disrupted

Dipole-dipole attractions are seen in interactions between:

any two polar molecules

How many orbitals are present in the (i) n = 2 and (ii) n = 4 shells? a. (i) 9 (ii) 16 b. (i) 4 (ii) 16 c. (i) 8 (ii) 32 d. (i) 3 (ii) 9 e. (i) 4 (ii) 8

b. (i) 4 (ii) 16

For BrCl3 the electron domain geometry is _______(i)________ and the molecular geometry is ______(ii)________? a. (i) trigonal planar; (ii) trigonal planar b. (i) Trigonal bipyramidal; (ii) T shaped c. (i) tetrahedral; (ii) trigonal planar d. (i) tetrahedral; (ii) trigonal pyramidal e. (i) Trigonal planar; (ii) tetrahedral

b. (i) Trigonal bipyramidal; (ii) T shaped

Consider the following processes: (i) freezing of liquid water (ii) combustion of a hydrocarbon (iii) rusting of iron (iv) explosive decomposition of sodium azide to inflate an automobile airbag (v) evaporation of diethyl ether Which of these processes are correctly referred to as a "physical change"? a. (i), (iii) and (v) b. (i) and (v) c. (ii), (iii) and (iv) d. (ii), (iii), (iv), and (v) e. (i), (iv) and (v)

b. (i) and (v)

Of the following, which are correctly referred to as "state functions"? (i) the heat change for a chemical reaction carried out at constant pressure (ii) straight line distance from Salt Lake City to Logan (iii) amount of work performed in the combustion of a gallon of gasoline (iv) calories burned in a 20 minute workout (v) number of students currently in this room a. all of the above are state functions b. (i), (ii) and (v) only c. (ii) and (v) only d. (i), (iii), and (iv) only e. (ii), (iii), (iv), and (v) only

b. (i), (ii) and (v) only

For the phase diagrams shown at right, the region indicated by _____ represents the liquid state, and diagram ____ can be predicted to be the phase diagram for water. a. (i); diagram 1 b. (ii); diagram 1 c. (iii); diagram 1 d. (ii); diagram 2 e. (iii); diagram 2

b. (ii); diagram 1

What is the oxidation number on P in the phosphite ion? (Hint- deduce the formula for the phosphite ion using the formula of the phosphate ion to guide you). a. +5 b. +3 c. +1 d. -1 e. -3

b. +3

Using the information in the table of average bond energies on page 1, estimate ΔH (in kJ) for the combustion of ethanol (be careful to use the right bond energy values and numbers of bonds): CH3CH2OH + 3O2 → 3H2O + 2CO2 a. +815 kJ b. -1255 kJ c. -1613 kJ d. +1726 kJ e. -1726 kJ

b. -1255 kJ

Calculate ΔH° for the combustion of propane (balanced equation shown below) using the data in the table of thermodynamic properties (note the physical states of reactants and products). C3H8(g) + 5O2(g) → 3CO2(g) + 4H2O(l) a. -531.5 kJ/mol b. -2220. kJ/mol c. +2220. kJ/mol d. +2044kJ/mol e. -2044 kJ/mol

b. -2220. kJ/mol

If you dissolve 0.30 moles of ammonium nitrate in 0.70 liters of solution, what is the total concentration, in moles/liter, of all of the ions present in solution? a. 0.43 M ions b. 0.86 M ions c. 0.21 M ions d. 0.42 M ions e. 0.30 M ions

b. 0.86 M ions

1.0 kg/cm3 equals ______ μg/m3. a. 1.0 x 10^11 b. 1.0 x 10^15 c. 1.0 x 10^12 d. 1.0 x 10^3 e. 1.0 x 10^-3

b. 1.0 x 10^15

If you dissolve 0.50 moles of LiCl in 0.75 liters of solution, what is the total concentration, in moles/liter, of all of the ions present in solution? a. 0.67 M ions b. 1.3 M ions c. 0.38 M ions d. 0.75 M ions e. 1.5 M ions

b. 1.3 M ions

You have 10.0 liters of an ideal gas at 5.00 atmospheres of pressure and at 37.0 degrees Celsius. What will be the new pressure of the gas if its volume is decreased to 4.00 liters while the temperature is increased to 100.0 degrees Celsius? a. 1.66 atm b. 2.41 atm c. 10.4 atm d. 33.8 atm e. 15.0 atm

b. 2.41 atm

What is the dissolved concentration of nitrogen in a fresh water stream in Logan, Utah when the atmospheric pressure is 0.855 atm. and the temperature is 25° C? The Henry's law constant for N2 is 6.10 x 10-4 M/atm and the mol fraction of N2 in air is 0.79. a. 5.64 x 10-4 M b. 4.12 x 10-4 M c. 5.22 x 10-4 M d. 9.03 x 10-4 M e. 6.60 x 10-4 M

b. 4.12 x 10-4 M

You have a 5.00 liter vessel that contains 2.00 g CO2, 3.00 g He, and 4.00 g N2 at 42° C. What is the total pressure in the vessel in atmospheres? a. 0.647 atm. b. 4.85 atm. c. 138 atm. d. 121 atm. e. 16.2 atm.

b. 4.85 atm.

Nitrogen and oxygen can be combined to produce nitrogen dioxide according to the following balanced chemical equation: N2(g) + 2 O2(g) → 2 NO2(g) ΔH° = __?__ kJ/mol reaction Under standard conditions and constant pressure, the reaction of 10.00 grams of O2 with excess N2 to produce NO2 was found to require the input of 10.37 kJ of heat. Use this information to determine the enthalpy change that should be reported for this reaction. a. 33.18 kJ b. 66.36 kJ c. 16.59 kJ d. 10.23 kJ e. 5.116 kJ

b. 66.36 kJ

A 15.0 liter vessel contains 7.50 moles of N2 at 4.00 atmospheres of pressure. What is the temperature of the vessel? a. 343 K b. 97.4 K c. 24.4 K d. 36.9 K e. 1.37 x 103 K

b. 97.4 K

For the heating curve shown at right, which letter corresponds to ΔHfusion? a. A b. B c. C d. D e. E

b. B

Which of the following elements would you predict to form a covalent network solid when solified from its standard state form? a. Ni b. C c. N d. O e. all of (b), (c) and (d)

b. C

The binary compound (HnX) of which of the following atoms would you predict has the lowest boiling point? a. N b. Si c. O d. S e. Se

b. Si

If red blood cells are diluted into a hypotonic solution (where the concentration of solutes is lower than the concentration of solutes present in the red blood cells) what will happen due to osmosis? a. Ions will move out of the cells causing the cells to shrivel b. Water will move into the cells causing the cells to swell c. Water will move out of the cells causing the cells to shrivel d. Ions will move into the cells causing the cells to swell e. Ions will move into the cells causing the cells to shrivel

b. Water will move into the cells causing the cells to swell

A chemical reaction that releases heat to the surroundings is said to be _____(i)_______ and has a ______(ii)_______ value of ΔH, while a chemical reaction that removes heat from the surroundings is said to be _____(iii)_______ and has a ______(iv)_______ value of ΔH (i) (ii) (iii) (iv) a. endothermic positive exothermic negative b. exothermic negative endothermic positive c. exothermic positive endothermic negative d. endothermic negative exothermic Positive e. endothermic negative exothermic negative

b. exothermic negative endothermic positive

Which of the following statements correctly states a consequence of the first law of thermodynamics? a. heat is always lost from the system to the surroundings for a spontaneous process b. in a chemical reaction, energy that is gained by the surroundings must equal the energy lost by the system c. a system always loses internal energy when it undergoes a chemical reaction d. both (a) and (c) are correct e. all of statements (a) to (c) are correct

b. in a chemical reaction, energy that is gained by the surroundings must equal the energy lost by the system

When sodium chloride is placed in water, it dissolves. The attraction between dissolved sodium chloride and water is referred to as: a. dipole-dipole attraction b. ion-dipole attraction c. London dispersion attraction d. hydrogen bonding attraction e. ionic bonding

b. ion-dipole attraction

For what type(s) of molecules are dipole-dipole attractions possible? a. neutral nonpolar molecules b. neutral polar molecules c. highly polarizable neutral nonpolar molecules d. all binary (XnYm) molecules where the bonded atoms have different electronegativities e. more than one of the above

b. neutral polar molecules

Draw a Lewis structure for CO. Then answer the following: the bonding in CO is best described by how many TOTAL bonds, and of which types: a. one sigma bond and three pi bonds b. one sigma bond and two pi bonds c. three pi bonds d. two sigma bonds and one pi bond e. one sigma bond and one pi bond

b. one sigma bond and two pi bonds

For the 4dyz orbital, the "d" specifies the orbital's: a. size b. shape c. orientation in space d. electron spin e. energy state

b. shape

For the 4dyz orbital, the "d" specifies the orbital's: a. size b. shape c. orientation in space d. electron spin e. energy state

b. shape

Which is the best definition of boiling point? a. the temperature at which molecules have sufficient kinetic energy to escape from the liquid to gas state. b. the temperature where the vapor pressure of a liquid becomes equal to the external pressure. c. the temperature at which gas bubbles form within in a liquid d. the temperature required to break the intermolecular attractions between molecules in the liquid. e. these are all correct definitions of boiling point.

b. the temperature where the vapor pressure of a liquid becomes equal to the external pressure.

Nitrous oxide, laughing gas, has the chemical formula N2O, where one N is a central atom and the other N and the O are terminal atoms. Draw possible Lewis structures for N2O. In the best Lewis structure based on formal charge considerations: a. there is a N-N double bond and a N-O double bond b. there is a N-N triple bond and a N-O single bond c. there is a N-N single bond and a N-O triple bond d. there is a N-N single bond and a N-O double bond e. there is a N-N double bond and a N-O single bond

b. there is a N-N triple bond and a N-O single bond

Which of the following cannot use hydrogen bonding as an intermolecular attractive force in a liquid solution of the molecule? a. they all can use hydrogen bonding b. three of them: i, iii, and vi c.four of them: i, ii, iii, and vi d. four of them: ii, iii, v and vi e. three of them: ii, iii, and vi

b. three of them: i, iii, and vi

Of the three types of molecular motion (translational, rotational, vibrational), which type of motion is most likely to be retained (still be present) after a gas is converted to a solid? a. translational b. vibrational c. rotational d. both translational and rotational e. both translational and vibrational

b. vibrational

For the following chemical reaction: 9 Cl2 + 2Na → 2 NaCl 38.0 g of Cl2 and 19.0 g of Na are combined and allowed to react. The limiting reactant will be ___(i)___, and the theoretical yield of NaCl will be ___(ii)____. a. (i) Cl2; (ii) 31.3 NaCl b. (i) Cl2; (ii) 62.6 g NaCl c. (i) Na; (ii) 48.3 g NaCl d. (i) Na; (ii) 24.1 mol NaCl e. (i) Cl2, (ii) 15.7 g NaCl

c. (i) Na; (ii) 48.3 g NaCl

When solidified from their standard state forms, C will form a _____(i)_____ solid; N will form a ___(ii)_____ solid; Ar will form a _____(iii)____ solid; and Sn will form a ___(iv)____ solid. a. (i) molecular; (ii) molecular; (iii) molecular; (iv) metallic b. (i) covalent network; (ii) covalent network; (iii) covalent network; (iv) metallic c. (i) covalent network; (ii) molecular; (iii) molecular; (iv) metallic d. (i) molecular; (ii) molecular; (iii) covalent network; (iv) metallic e. (i) molecular; (ii) molecular; (iii) molecular; (iv) covalent network

c. (i) covalent network; (ii) molecular; (iii) molecular; (iv) metallic

The addition of a solute to water will result in freezing point ____(i)_______ , boiling point _____(ii)______ , and vapor pressure _______(iii)_____. a. (i) depression (ii) depression (iii) elevation b. (i) depression (ii) elevation (iii) elevation c. (i) depression (ii) elevation (iii) depression d. (i) elevation (ii) depression (iii) depression e. (i) elevation (ii) depression (iii) elevation

c. (i) depression (ii) elevation (iii) depression

The addition of a solute to water will result in vapor pressure ____(i)_______ , boiling point _____(ii)______ , and freezing point _______(iii)_____. a. (i) depression (ii) depression (iii) elevation b. (i) depression (ii) elevation (iii) elevation c. (i) depression (ii) elevation (iii) depression d. (i) elevation (ii) depression (iii) depression e. (i) elevation (ii) depression (iii) elevation

c. (i) depression (ii) elevation (iii) depression

A chemical reaction in which heat is transferred from the surroundings to the system of interest is said to be _____(i)_______ and has a ______(ii)_______ value of ΔH, while a chemical reaction in which heat is transferred from the system to the surroundings is said to be _____(iii)_______ and has a ______(iv)_______ value of ΔH a. (i) endothermic; (ii) negative; (iii) exothermic; (iv) positive; b. (i) exothermic; (ii) negative; (iii) endothermic; (iv) positive; c. (i) endothermic; (ii) positive; (iii) exothermic; (iv) negative; d. (i) exothermic; (ii) positive; (iii) endothermic; (iv) negative;

c. (i) endothermic; (ii) positive; (iii) exothermic; (iv) negative;

For a phase diagram, the point at which all states of matter can coexist is called the ____(i)_______ point, and the point at which a gas can no longer be distinguished from a liquid is called the ______(ii)______ point. a. (i) equilibrium; (ii) critical b. (i) critical; (ii) equilibrium c. (i) triple; (ii) critical d. (i) critical; (ii) triple e. (i) transition; (ii) equilibrium

c. (i) triple; (ii) critical

Of the following molecules, which cannot use dipole-dipole attractions as an intermolecular attractive force? (i) AsH3 (ii) SO3 (iii) CS2 (iv) H2Se a. (i), (ii), and (iii) b. (i), (ii), and (iv) c. (ii) and (iii) d. (i), (ii), (iii), and (iv) e. (iii)

c. (ii) and (iii)

Consider the following processes: (i) freezing of liquid water (ii) combustion of a hydrocarbon (iii) rusting of iron (iv) explosive decomposition of sodium azide to inflate an automobile airbag (v) evaporation of diethyl ether Which of these processes are correctly referred to as a "chemical change"? a. (i), (iii) and (v) b. (i) and (v) c. (ii), (iii) and (iv) d. (ii), (iii), (iv), and (v) e. (i), (ii), and (v)

c. (ii), (iii) and (iv)

What is the oxidation number of C in the oxalate ion, H2C2O4? a. +4 b. +6 c. +3 d. +2 e. -2

c. +3

During the course of a chemical reaction, the system releases 30.0 kJ of heat to the surroundings and the surroundings perform 20.0 kJ of work on the system. What is the energy change for the system? a. -50.0 kJ b. +10.0 kJ c. -10.0 kJ d. +50.0 kJ

c. -10.0 kJ

Given the data below, determine ΔH° for the reaction: C(s) + 2H2(g) CH4(g) C(s) + O2(g) CO2(g) ΔH° = -393.5 kJ H2(g) + ½ O2(g) H2O (l) ΔH° = -285.8 kJ CH4(g) + 2O2(g) CO2(g) + 2H2O (l) ΔH° = -890.3 kJ a. -211 kJ/mol b. -1855.4 kJ/mol c. -74.8 kJ/mol d. +211.0 kJ/mol e. -1569.6 kJ/mol

c. -74.8 kJ/mol

What will be the freezing point of a solution prepared by dissolving 95.0 grams of NaCl in 755 g of water? The molal freezing-point depression constant for water is 1.86°C/m. a. -4.00 °C b. -2.00 °C c. -8.01 °C d. -3.02 °C e. -6.05 °C

c. -8.01 °C

A solution was prepared by placing 11 g of sucrose, C12H22O11, in a flask and adding water to make a final volume of 0.25 L of solution. The concentration of sucrose in the solution is a. 0.0080 M b. 7.8 M c. 0.13 M d. 44 M e. 0.032 M

c. 0.13 M

A 10.8 liter container contains 0.500 moles of gas at a temperature of 55.6°C. What is the pressure in the container? a. 0.211 atm b. 583 atm c. 1.25 atm d. 98.5 atm e. 0.200 atm

c. 1.25 atm

For the combustion of the hydrocarbon pentene (C5H10) in air, what is the coefficient in front of H2O when the chemical equation for the reaction is properly balanced? a. 5 b. 7 c. 10 d. 15 e. 14

c. 10

In the Lewis structure for IBr4 - , I has ___(i)_____ lone pairs of electrons and _____(ii)______bonded pairs of electrons. a. 0, 4 b. 1, 4 c. 2, 4 d. 4, 8 e. 4, 1

c. 2, 4

You have a 5.00 liter balloon containing an ideal gas at 1.50 atmospheres of pressure and at 30.0 degrees Celsius. What will be the new pressure of the balloon if its volume is decreased to 2.70 liters while the temperature is decreased to 10.0 degrees Celsius? a. 8.33 atm b. 0.926 atm c. 2.97 atm d. 2.59 atm e. 0.757 atm

c. 2.59 atm

Ethanol , C2H6O, burns readily in oxygen via a combustion reaction, producing CO2 and water. When the reaction for the combustion of ethanol is properly balanced, what is the coefficient in front of O2? a. 1 b. 2 c. 3 d. 4 e. 7

c. 3

Gold has a density of 19.30 g/cm3. You have a graduated cylinder containing 50.0 mL of water. You add a chunk of pure gold to the water, and the volume of the graduated cylinder increases to 75.4 mL. What is the mass of the chunk of gold? a. 1.46 x 102 g b. 1.32 g c. 490. g d. 3.91 g e. 29.1 g

c. 490. g

One mol of a certain type of electromagnetic radiation has an energy equal to that of a banana (290.0 kJ). What frequency does this particular radiation have? a. 7.27 x 10^11 hz b. 2.63 × 10^62 hz c. 7.27 x 10^14 hz d. 4.38 × 10^38 hz e. 4.38 × 10^35 hz

c. 7.27 x 10^14 hz

A 5.00-liter vessel contains 12.0 grams of N2, 5.00 grams of CO2, and 2.00 grams of H2 at 27.0° C. What is the total pressure in the vessel? a. 12.4 atm. b. 0.680 atm. c. 7.56 atm. d. 80.3 atm. e. 1.12 atm.

c. 7.56 atm.

Order the following atoms from highest to lowest first-ionization energy: Cl, S, Se, Sb a. S > Cl > Se > Sb b. Cl > Se > S > Sb c. Cl > S > Se > Sb d. Sb >Se > S > Cl

c. Cl > S > Se > Sb

Which type of intermolecular attractive force can result from the formation of an instantaneous dipole? a. ion-dipole b. dipole-dipole c. London dispersion d. hydrogen bonding e. more than one of the above

c. London dispersion

Which of the following is a correct definition of osmosis? a. Movement of solute across a semi-permeable membrane from the side with lower solute concentration to the side with higher solute concentration b. Movement of solute across a semi-permeable membrane from the side with higher solute concentration to the side with lower solute concentration c. Movement of solvent across a semi-permeable membrane from the side with lower solute concentration to the side with higher solute concentration d. Movement of solvent across a semi-permeable membrane from the side with higher solute concentration to the side with lower solute concentration e. absorption of chemical information by sleeping with your head resting on your textbook

c. Movement of solvent across a semi-permeable membrane from the side with lower solute concentration to the side with higher solute concentration

Which one of the following molecules would you predict to be polar? a. ICl4- b. CCl4 c. SF4 d. BH3 e. CO2

c. SF4

Which of the following systems is not an example of a "dynamic equilibrium" a. vapor pressure exerted by a liquid in a sealed flask b. a saturated aqueous solution of NaCl containing undissolved NaCl c. boiling of water at 100 °C d. the amount of air dissolved in water at 25° C and 1 atmosphere pressure e. these are all examples of dynamic equilibria.

c. boiling of water at 100 °C

Which of the following statements is not correct for the kinetic-molecular theory of gases? a. The volume occupied by gas molecules is much less than the volume in which they reside b. There are no significant attractive/repulsive forces between gas molecules c. different gases (for example, Ar, N2, He) at a given temperature will have the same average velocities d. Gas molecules collide with each other and walls of container without loss of energy e. The average kinetic energy of a gas molecule is directly proportional to the temperature

c. different gases (for example, Ar, N2, He) at a given temperature will have the same average velocities

Draw a Lewis structure for CO. Then answer the following: the bonding in CO is best described by how many TOTAL bonds, and of which types: a. three sigma bonds b. three pi bonds c. one sigma bond and two pi bonds d. two sigma bonds and one pi bond e. one sigma bond and one pi bond

c. one sigma bond and two pi bonds

How many orbitals are present in the (i) n = 3 and (ii) n = 4 shells? a. (i) 16 (ii) 32 b. (i) 4 (ii) 9 c. (i) 18 (ii) 32 d. (i) 9 (ii) 16 e. (i) 6 (ii) 8

d. (i) 9 (ii) 16

During the solution process, disruption of solute-solute interactions is _____(i)_______, disruption of solvent-solvent interactions is ______(ii)_____, and formation of solute-solvent interactions is _____(iii)______. a. (i) endothermic (ii) exothermic (iii) exothermic b. (i) endothermic (ii) exothermic (iii) endothermic c. (i) exothermic (ii) endothermic (iii) exothermic d. (i) endothermic (ii) endothermic (iii) exothermic e. (i) exothermic (ii) exothermic (iii) endothermic

d. (i) endothermic (ii) endothermic (iii) exothermic

When solidified from their standard state forms, O will form a _____(i)_____ solid; Xe will form a ___(ii)_____ solid; C will form a _____(iii)____ solid; and Sn will form a ___(iv)____ solid. a. (i) molecular; (ii) molecular; (iii) molecular; (iv) metallic b. (i) covalent network; (ii) molecular; (iii) molecular; (iv) metallic c. (i) covalent network; (ii) molecular; (iii) covalent network; (iv) metallic d. (i) molecular; (ii) molecular; (iii) covalent network; (iv) metallic e. (i) molecular; (ii) metallic; (iii) molecular; (iv) covalent network

d. (i) molecular; (ii) molecular; (iii) covalent network; (iv) metallic

For the phase diagrams shown at right, the region indicated by _____ represents the liquid state, and diagram ____ can be predicted to be the phase diagram for carbon dioxide. a. (i); diagram 1 b. (ii); diagram 1 c. (iii); diagram 1 d. (ii); diagram 2 e. (iii); diagram 2

d. (ii); diagram 2

For the combustion of the hydrocarbon hexane (C6H14) in air, what is the coefficient in front of H2O when the chemical equation for the reaction is properly balanced? a. 6 b. 7 c. 12 d. 14 e. 4

d. 14

Calculate the vapor pressure of water above a solution prepared by dissolving 10.0 g of sucrose, C12H22O11, in 82.0 g of water at 25°C. The vapor pressure of pure water at 25°C is 23.8 torr. a. 0.153 torr b. 2.90 torr c. 21.2 torr d. 23.6 torr

d. 23.6 torr

How many equivalent resonance structures can be drawn for the sulfate ion drawn in the form where the central S atom bears a formal charge of 0? a. only one b. 2 c. 4 d. 6 e. 8

d. 6

An elemental ion has 34 protons, 36 electrons, and 44 neutrons. What isotope is it? a. 80Kr b. 78Se c. 78Se2+ d. 78Se2- e. 80Kr2+-

d. 78Se2-

For the heating curve shown at right, which letter corresponds to ΔHvaporizaton? a. A b. B c. C d. D e. E

d. D

Valence shell electron pair repulsion (VSEPR) theory is based on the idea that a. atoms in molecules are restricted to 4 bonds, or 8 total electrons around each atom. b. Electron pairs about an atom arrange themselves in such a fashion as to maximize the interaction between each pair. c. nonbonded (lone) electron pairs require less space than bonded electron pairs. d. Electron pairs arrange themselves in such a fashion as to minimize the interaction between each electron pair. e. both (c) and (d) are correct

d. Electron pairs arrange themselves in such a fashion as to minimize the interaction between

Consider the following compounds, all of which are soluble in water: I II III IV V Glucose, C6H12O6 hydrochloric acid, HCl Glycerol, C3H8O3 Acetic acid, HC2H3O2 Ammonium carbonate, (NH4)2CO3 Which of these compounds would you expect to behave as strong electrolyte(s) in solution? a. I and IV only b. I, III, and IV only c. II and IV only d. II and V only e. II, IV, and V only

d. II and V only

A certain elemental ion that is isoelectronic with Ar has valence electrons that feel Zeff = +5. This ion could be formed from which atom? a. K b. S c. Ca d. P e. more than one of the above

d. P

Under which of the following conditions would you expect a gas to deviate most from behaving like an ideal gas? a. low pressure and high temperature b. high pressure and high temperature c. low pressure and low temperature d. high pressure and low temperature

d. high pressure and low temperature

What hybrid orbital set would be used for the central atom of a molecule that has a see saw molecular geometry? a. sp b. sp2 c. sp3 d. sp3d e. sp3d2

d. sp3d

Which statement is correct for a saturated solution of sodium chloride, NaCl: a. undissolved NaCl will no longer undergo the dissolving process b. dissolved NaCl will no longer undergo precipitation c. the solubility of NaCl can be increased by lowering the temperature. d. the rate of NaCl dissolving is equal to the rate of NaCl precipitating. e. the strength of solvent-solvent interactions is equal to the strength of solute-solute interactions

d. the rate of NaCl dissolving is equal to the rate of NaCl precipitating.

Which of the following is an incorrectly stated relationship between two variables for an ideal gas? a.T∝1 V b..VP∝1 c..n∝1 V d..TP∝1 e. all the relations are correct

d..TP∝1

For ClF3 the electron domain geometry is _______(i)________ and the molecular geometry is ______(ii)________? a. (i) trigonal planar; (ii) trigonal planar b. (i) tetrahedral; (ii) trigonal pyramidal c. (i) tetrahedral; (ii) trigonal planar d. (i) Trigonal planar; (ii) tetrahedral e. (i) Trigonal bipyramidal; (ii) T shaped

e. (i) Trigonal bipyramidal; (ii) T shaped

Using the information in the table of average bond energies, estimate ΔH (in kJ) for the combustion of ethanol (be careful to use the right bond energy values and numbers of bonds): CH3CH2OH + 3O2 → 3H2O + 2CO2 a. +815 kJ b. +1726 kJ c. -1613 kJ d. -1726 kJ e. -1255 kJ

e. -1255 kJ

Calculate ΔH° for the combustion of propane (balanced equation shown below) using the data in the table of thermodynamic properties (note the physical states of reactants and products). C3H8(g) + 5O2(g) → 3CO2(g) + 4H2O(g) a. -531.5 kJ/mol b. +2220. kJ/mol c. -2220. kJ/mol d. +2044kJ/mol e. -2044 kJ/mol

e. -2044 kJ/mol

You have 250.0 mL of 0.500 M methanol which you dilute to a final volume of 600.0 mL by adding water. What is the new concentration of methanol in the diluted solution? a. 0.833 M b. 0.417 M c. 0.0750 M d. 0.300 M e. 0.208 M

e. 0.208 M

A banana contains about 290. kJ of energy. Visible light was used as the source of energy in photosynthesis to make that banana. How many photons of visible red light with a frequency of 4.29 x 1014 Hz would provide 290. kJ of energy? a. 6.25 x 1044 photons b. 1.21 x 1016 photons c. 1.31 x 1038 photons d. 2.08 x 1018 photons e. 1.02 x 1024 photons

e. 1.02 x 1024 photons

You prepare a solution by placing 325 g of ammonium phosphate in a flask and adding water such that the final volume in the solution is 1.20 liters. What is the concentration of ammonium phosphate in the solution? a. 2.62 M b. 0.290 M c. 0.382 M d. 2.40 M e. 1.82 M

e. 1.82 M

What is the boiling point at sea level (1 atm. pressure) of a solution prepared by dissolving 40.0 g of NaCl in 250.0 g of water? Kb for H2O is 0.510 °C/m. a. 106.0 °C b. 98.6 °C c. 101.4 °C d. 97.2 °C e. 102.8 °C

e. 102.8 °C

Calculate the vapor pressure in a sealed flask containing 55.0 g of ethylene glycol, C2H6O2, dissolved in 155 g of water at 25.0°C. The vapor pressure of pure water at 25.0°C is 23.8 torr. a. 21.1 torr b. 2.45 torr c. 21.3 torr d. 2.22 torr e. 21.6 torr

e. 21.6 torr

It takes 2221 kJ of energy to synthesize one mol of sucrose. How many photons of light with a wavelength of 430.0 nm would a plant have to absorb to provide this amount of energy? a. 1.92 x 10^15 b. 9.74 x 10^17 c. 2.34 x 10^54 d. 4.32 x 10^38 e. 4.80 x 10^24

e. 4.80 x 10^24

Alkali metals are highly reactive when exposed to water, undergoing oxidation as shown for sodium in the following balanced chemical equation: 2Na(s) + 2H2O(l) → 2NaOH (aq) + H2(g) What volume of hydrogen gas will be produced from the reaction of 10.0 grams of sodium with excess water at 25.0° C and 650 torr? a. 9.10 L b. 12.4 L c. 24.9 L d. 4.55 L e. 6.22 L

e. 6.22 L

An element in the periodic table gains three electrons, which results in an ion with 36 electrons. The element also has 42 neutrons. What is the correct symbol for this ion? a. 75Y3- b. 75Y3+ c. 78As3- d. 78Y3+ e. 75As3-

e. 75As3-

An element in the periodic table gains three electrons, which results in an ion with 36 electrons. The element also has 42 neutrons. What is the correct symbol for this ion? a. 75Y^3- b. 75Y^3+ c. 78As^3- d. 78Y^3+ e. 75As^3-

e. 75As^3-

How many electrons can occupy the (i) n = 2, (ii) n = 3 and (iii) n = 4 shells? (i) (ii) (iii) a. 3 9 16 b. 6 18 32 c. 4 6 8 d. 4 9 16 e. 8 18 32

e. 8 18 32

Under standard conditions, the reaction of 10.0 mol of H2 with excess N2 produces 308 kJ of heat. Use this information to determine the enthalpy change associated with the following reaction, as written, in units of kJ/mol. 3H2(g) + N2(g) 2NH3(g) ΔH° = __?__ kJ/mol reaction a. 205 kJ/mol b. 4.62 x 103 kJ/mol c. 30.8 kJ/mol d. 46.2 kJ/mol e. 92.4 kJ/mol

e. 92.4 kJ/mol

If 7.0 moles of O2 and 8.0 moles of Al are used in the reaction: then the limiting reactant is _________ and the theoretical yield of Al2O3 is ____________ mol. a. O2, 2.3 mol Al2O3 b. O2, 7.0 mol Al2O3 c. Al, 2.0 mol Al2O3 d. Al, 1.0 mol Al2O3 e. Al, 4.0 mol Al2O3

e. Al, 4.0 mol Al2O3

What is the empirical formula of a compound that contains 62.0% C, 10.4% H, and 27.6% O by mass a. CH2O b. C3H6O2 c. CH4O d. C3H4O e. C3H6O

e. C3H6O

Which of the following is a correct definition of osmosis? a. absorption of chemical information by sleeping with your head resting on your textbook. b. Movement of solute across a semi-permeable membrane from the side with higher solute concentration to the side with lower solute concentration c. Movement of solute across a semi-permeable membrane from the side with lower solute concentration to the side with higher solute concentration d. Movement of solvent across a semi-permeable membrane from the side with higher solute concentration to the side with lower solute concentration e. Movement of solvent across a semi-permeable membrane from the side with lower solute concentration to the side with higher solute concentration

e. Movement of solvent across a semi-permeable membrane from the side with lower solute concentration to the side with higher solute concentration

Referring to the following bonds, which order is correct for increasing polarity (least polar first)? Si-F Si-Cl S-Cl P-Cl a. Si-F < Si-Cl < P-Cl < S-Cl b. S-Cl < P-Cl < Si-Cl < Si-F c. P-Cl < S-Cl < Si-Cl < Si-F d. S-Cl < P-Cl < Si-F < Si-Cl e. Si-F < P-Cl < Si-Cl < S-Cl

e. Si-F < P-Cl < Si-Cl < S-Cl

The fact that HCl has a slightly lower boiling point than HBr is due to: a. greater electronegativity of Br over Cl b. greater London-dispersion forces in HCl c. greater dipole-dipole attractions in HBr d. greater electronegativity of Cl over Br e. greater London-dispersion forces in HBr

e. greater London-dispersion forces in HBr

Of the following, which are both endothermic processes? a. vaporization and freezing b. condensation and freezing c. sublimation and condensation d. deposition and melting e. vaporization and sublimation

e. vaporization and sublimation

For the 4dyz orbital, the "4" specifies the orbital's?

energy

Which of the following cannot use hydrogen bonding as an intermolecular attractive force in a liquid solution of the molecule? H2O C O H CH3 C O H3C O H i ii iii iv v vi NH3 C O H3C O CH3 H H

iii, iv, and vi

For which electronic transition does a hydrogen atom emit electromagnetic radiation with the longest wavelength?

n = 4 to n = 3

For the 4dyz orbital, the "yz" specifies the orbital's?

orientation in space

For the 4dyz orbital, the "d" specifies the orbital's?

shape