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True/False Questions

1) Stoichiometry is a chemist's version of following a recipe.

2) Given the reaction: 2 Na(s) + Cl2(g) → 2 NaCl(s)

The conversion factor for chlorine gas to sodium metal is: 2 mol Cl ≡ 2 mol Na

3) The limiting reactant is the product that is completely consumed in a chemical reaction.

4) Li : is the proper Lewis structure (dot structure) for lithium.

5) Lewis theory predicts that the formula for a compound made of aluminum and phosphorus is AlP.

6) The correct Lewis structure for CO2 shows that the carbon atom has two sets of lone pair electrons.

7) The VSEPR theory predicts that the H-C-H angle in CH4 measures 120°.

8) When you have 4 electron groups and 1 of them is a lone pair, the molecular geometry is bent.

9) Water and oil do not mix because water molecules are nonpolar and molecules that compose oil are generally polar.

10) The scientific method emphasizes reason as the way to understand the world.

11) Theories can be tested and validated through experimentation.

12) The mass of an object, 4.55 × g, expressed in decimal notation is 0.000455 g.

13) When the number 65.59 is rounded to contain 2 significant figures, it becomes 66.0.

14) Conversion factors are constructed from any two quantities known to be equivalent.

15) Liquid and gas molecules can easily be compressed, while in a solid the molecules are incompressible.

16) A chemical change occurs when matter does not change its composition.

17) When a cold ice cube is dropped into a warm cup of water, energy is transferred as heat from the ice to the water.

18) All of the positive charge of an atom is concentrated in the nucleus.

19) The number of protons in an atom's nucleus defines the element.

20) Halogens form anions with a 1- charge.

21) The fact that water has an oxygen-to-hydrogen mass ratio of 8.0 illustrates the law of conservation of mass.

22) The ionic compound that forms between aluminum and oxygen is AlO.

23) Ionic compounds are usually made up of a metal and a nonmetal.

24) The formation of a gas is evidence of a chemical reaction while the emission of light is not.

25) The following equation IS balanced: CH4 + 2O2 → CO2 + H2O

26) The following equation IS balanced: HNO3 + NaHSO3 → NaNO3 + H2O + SO2

27) Li+, Na+, K+ and NH4+ compounds are soluble.

28) The reaction 2 KClO3 → 2 KCl + 3 O2 would be correctly classified as a decomposition reaction.

29) The shorter the wavelength of light, the more energy it has.

30) An orbital is a probability map showing exactly where an electron can be found in an atom.

31) The number 6.022 × is six times larger than the number 6.022 × .

32) One mole of water contains 16 grams of oxygen atoms.

33) The molar mass of a compound in grams per mole is numerically equal to the formula mass of the compound in atomic mass units.

34) As we climb a mountain to a higher altitude, we experience a pressure decrease.

35) For all gas law calculations, the temperature must be in kelvins.

36) Intermolecular forces are the attractive forces between atoms within a compound.

37) Increasing the temperature increases the vaporization rate of a liquid because the excess energy is used to break covalent bonds.

38) Dipole-dipole forces are weaker than dispersion forces.

39) Ionic solids tend to have higher melting points than molecular solids.

40) Ice can float in a glass of liquid water because the solid form of water is more dense than the liquid form.

41) A solution is a homogeneous mixture of two or more substances.

42) A saturated solution holds the maximum amount of solute under the solution conditions.

43) One liter of 6.0 M HNO3 contains the same number of H+ ions as does one liter of 6.0 M H2SO4.

44) A 1.0 M [H3O+] solution of a strong acid would have a pH equal to zero.

45) A solution that has a pH of 8.5 is considered a weak base.

46) A buffer resists a change in pH by being able to react with an acid or a base.

47) The rate of a chemical reaction is the amount of reactant that changes to product in a specific amount of time.

48) When dynamic equilibrium is achieved, the concentrations of reactants is equal to the concentrations of the

products.

49) The Equilibrium Constant, , is a way to quantify the relative concentrations of the reactants and products of a

reaction at equilibrium.

50) For a given chemical equation, the coefficients for each substance become the exponents for each substance in the written equilibrium expression.

Multiple Choice Questions

1) How many eggs are needed to make 1 dozen waffles, assuming you have enough of all other ingredients? Given: 2 cups flour + 3 eggs + 1 tbs oil → 4 wafflesA) 48 B) 9C) 12D) 16E) not enough information

2) How many waffles can be made from 1 dozen eggs, assuming you have enough of all other ingredients?Given: 2 cups flour + 3 eggs + 1 tbs oil → 4 wafflesA) 48 B) 12C) 4D) 16E) not enough information

3) Diatomic N2 can react with diatomic H2 to form ammonia (NH3). The balanced chemical equation is:

If 6 moles of H2 totally reacted with more than enough N2, how many moles of ammonia would be expected to

form?A) 2 molesB) 3 molesC) 4 molesD) 6 molesE) not enough information

4) Diatomic O2 can react with the element magnesium to form magnesium oxide (MgO). The balanced chemical

equation is:

If 4 moles of magnesium totally reacted with more than enough O2, how many moles of MgO would be expected to

form?A) 1 moleB) 2 molesC) 4 molesD) 8 molesE) not enough information

5) How many moles of water are made from complete reaction of 2.2 moles of oxygen gas with hydrogen gas?

Given the reaction: 2H2 + O2 → 2H2O

A) 4.4B) 1.1C) 2.2D) 3.3E) not enough information

6) How many moles of H2 can be made from complete reaction of 3.0 moles of Al?

Given: 2 Al + 6 HCl → 2 AlCl3 + 3 H2

A) 3 molesB) 3.0 molesC) 4.5 molesD) 9.0 molesE) none of the above

7) How many moles of chlorine gas are needed to make 0.6 moles of sodium chloride?

Given the reaction: 2Na + Cl2 → 2NaCl


8) How many moles of sodium metal are needed to make 3.6 moles of sodium chloride?

Given the reaction: 2Na + Cl2 → 2NaCl


9) Given the balanced equation CH4 + 2 O2 → CO2 + 2 H2O, which of the following is NOT a correct conversion

factor?

A) 2 mole H2O = 18.02 g

B) 1 mole O2 = 32.00 g

C) 1 mole CH4 2 mole H2O

D) 2 mole O2 1 mole CO2

E) none of the above

10) How many grams of water are made from the reaction of 16.0 grams of oxygen gas?

Given the reaction: 2H2 + O2 → 2H2O

A) 18

B) 9C) 36D) 16E) not enough information

11) Many metals react with halogens to give metal halides. For example, 2 Al (s) + 3 Cl2(g) → 2 AlCl3 (s)

If you begin with 13.5 g of aluminum:A) you will need 23.6 g Cl2 for complete reaction and will produce 66.7 g of AlCl3.B) you will need 53.2 g Cl2 for complete reaction and will produce 66.7 g of AlCl3.C) you will need 26.6 g Cl2 for complete reaction and will produce 49.0 g of AlCl3.D) you will need 11.8 g Cl2 for complete reaction and will produce 49.0 g of AlCl3.E) none of the above

12) A chemist wishes to perform the following reaction: N2 + 3 H2 → 2 NH3If only 14.0 g of N2 is available, what is the minimum amount, in grams, of H2 needed to completely react with this quantity of N2?A) 1.01 gB) 1.51 gC) 3.03 gD) 6.06 gE) none of the above

13) Which ingredient is the limiting reactant if you have 6 cups of flour, 9 eggs and 2 tbs of oil? Given: 2 cups flour + 3 eggs + 1 tbs oil → 4 wafflesA) flourB) eggsC) oilD) wafflesE) not enough information

14) Consider the following generic chemical equation: 2A + 5B → C + 3DIf you react 4 units of A with 10 units of B, which statement is TRUE?A) Substance A will be the limiting reactant.B) Substance B will be the limiting reactant.C) There is just enough of A and B so that everything reacts completely.D) Substance C cannot be formed from this reaction.E) none of the above

15) What is the excess reactant for the following reaction given we have 3.4 moles of Ca(NO3)2 and 2.4 moles of

Li3PO4?

Reaction: 3Ca(NO3)2 + 2Li3PO4 → 6LiNO3 + Ca3(PO4)2

A) Ca(NO3)2

B) Li3PO4

C) LiNO3

D) Ca3(PO4)2

E) not enough information

16) How many grams of NO2 are theoretically produced if we start with 1.20 moles of S and 9.90 moles of HNO3?

Reaction: S + 6HNO3 → H2SO4 + 6NO2 + 2H2O

A) 7.20B) 331C) 455D) 786E) not enough information

17) How many moles of calcium chloride are theoretically produced for the following reaction given we have 2.6

moles of HCl and 1.4 moles of Ca(OH)2?

Reaction: 2HCl + Ca(OH)2 → 2H2O + CaCl2


18) How many moles of aluminum oxide are produced according to the reaction below given that you start with

10.0 grams of Al and 19.0 grams of O2?

Reaction: 4Al + 3O2 → 2Al2O3


19) How many grams of aluminum oxide are produced according to the reaction below given that you start with

10.0 grams of Al and 19.0 grams of O2?

Reaction: 4Al + 3O2 → 2Al2O3


20) A 24.0 g sample of nitrogen gas reacts with an excess of hydrogen gas to give an actual yield of NH3.

What is the percent yield for this reaction?

Reaction: N2(g) + 3 H2(g) → 2 NH3(g)

A) 86.8%B) 73.6%C) 26.4%D) 13.2%E) none of the above

21) What is the theoretical yield in grams of CuS for the following reaction given that you start with of Na2S

and CuSO4?

Reaction: Na2S + CuSO4 → Na2SO4 + CuS


22) How many moles of water are needed to react with 2.2 moles of O?

Given: O + O → 2 LiOH

A) 4.4B) 1.1C) 1.5D) 2.2E) none of the above

23) Consider the reaction: 2 Al + 3Br2 → 2 AlBr3

Suppose a reaction vessel initially contains 5.0 mole Al and 6.0 mole Br2. What is in the reaction vessel once the

reaction has occurred to the fullest extent possible?

A) 1.0 mole Al; 0 mole Br2; 4.0 mole AlBr3

B) 0 mole Al; 0 mole Br2; 11.0 mole AlBr3

C) 2.0 mole Al; 3.0 mole Br2; 2.0 mole AlBr3

D) 0 mole Al; 1.0 mole Br2; 4.0 mole AlBr3


24) Which is the limiting reactant in the following reaction given that you start with of CO2 and KOH?

Reaction: CO2 + 2KOH → K2CO3 + H2O

A) K2CO3

B) H2O

C) CO2

D) KOHE) not enough information

25) Consider a reaction of chemicals depicted as A + B → C + D. Suppose reaction of 17.8 grams of A with 29.5 grams of B gave 24.7 grams of C. However, the theoretical yield of C for this reaction was 33.3 grams. What was the percent yield of chemical C?A) 74.2B) 47.3C) 11.7D) 135E) none of the above

26) Which Lewis structure below correctly represents the compound formed between magnesium and sulfur?

A) Mg⁺ [: :]⁻

B) Mg⁺ [: :]⁻2 Mg⁺

C) [: :]⁻ Mg⁺2 [: :]⁻

D) Mg⁺2 [: :]⁻2


27) The Lewis model predicts that the formula of a compound formed between bromine and aluminum is:A) AlBr

B) Al2Br

C) AlBr3

D) AlBr2


28) What is the correct Lewis structure for water?

A) H-: :-H

B) : - - :

C) H= =H

D) H- -HE) none of the above

29) What is the correct Lewis structure for N2?

A) N-N

B) : - :

C) =D) : N ≡ N :


30) How many bonding electrons are in the Lewis structure of carbon monoxide, CO?A) 2B) 3C) 4D) 6E) none of the above

31) The total number of electrons to be counted for the Lewis structure of the PO43- polyatomic ion is:

A) 8.B) 26.C) 29.D) 32.E) none of the above

32) The central atom in the chlorate anion, ClO3- is surrounded by:

A) two bonding and two unshared pairs of electrons.B) one bonding and three unshared pairs of electrons.C) three bonding and one unshared pair of electrons.D) two double bonds and no unshared pairs of electrons.E) none of the above.

33) The central atom in the chlorite anion, ClO2- is surrounded by:

A) one bonding and three unshared pairs of electrons.B) two bonding and two unshared pairs of electrons.C) two bonding and one unshared pair of electrons.D) two double bonds and no unshared pairs of electrons.E) none of the above

34) What is the correct Lewis structure for CN⁻?A) [C-N]⁻

B) [: - :]⁻

C) [ = :]⁻D) [: C ≡ N :]⁻E) none of the above

35) The correct Lewis structure for BF3 would have exactly:

A) 1 double bond.B) 2 double bonds.C) 1 triple bond.D) no double bonds.E) none of the above

36) Which molecule below would have a Lewis structure that is an exception to the octet rule?

A) BH3

B) NO

C) SI6

D) PF5

E) all of these

37) What is the angle between electron groups in the linear electron geometry?A) 90°B) 109.5°C) 120°D) 180°E) not enough information

38) What is the angle between electron groups in the tetrahedral geometry?A) 90°B) 109.5°C) 120°D) 180°E) not enough information

39) What is the electron geometry if you have 4 electron groups around the center atom?A) linearB) trigonal planarC) tetrahedralD) trigonal bipyramidalE) not enough information

40) What is the molecular geometry if you have 3 single bonds and 1 lone pair around the central atom?

A) bentB) linearC) tetrahedralD) trigonal pyramidalE) not enough information41) What is the molecular geometry if you have a double bond, a single bond and 1 lone pair around the central atom?A) bentB) linearC) tetrahedralD) trigonal pyramidalE) not enough information

42) What is the molecular geometry of PH3?

A) bentB) linearC) tetrahedralD) trigonal pyramidalE) not enough information

43) Which of the following has a tetrahedral electron geometry and a trigonal pyramidal molecular geometry?

A) Br2O

B) GeH4

C) SO2

D) PF3


44) The elements with the highest electronegativity values tend to be found in the:A) upper right-side of the periodic table.B) lower right-side of the periodic table.C) upper left-side of the periodic table.D) lower left-side of the periodic table.E) center of the periodic table.

45) Which molecule listed below is a polar molecule?

A) NH3

B) H2O

C) HCND) all of the compoundsE) none of the compounds

46) Which compound listed below will dissolve in water?

A) CCl4

B) SiO2

C) NH3

D) all of the compoundsE) none of the compounds

47) Which compound listed below will dissolve in carbon tetrachloride, CCl4?

A) NaCl

B) CS2

C) NH3

D) all of the compoundsE) none of the compounds

48) The electronegativity value for N is 3.0 and that for O is 3.5. Based on these values, which of the following statements is TRUE about the compound NO?A) NO is an ionic compound.B) NO is a pure covalent compound.C) NO is a polar covalent compound.D) There is not enough enough information to determine the nature of NO.E) None of the above statements is true.

49) Which compound below is a polar molecule AND has a linear molecular geometry?A) CO

B) CO2

C) CH4

D) H2O


50) How many lone electron pairs does the ClO (-1 charged) polyatomic anion have?A) oneB) threeC) sixD) twoE) none of the above

51) A good definition of chemistry is:A) the science that seeks to understand what matter does by studying what atoms and molecules do.B) the science that seeks to understand what living organisms do by studying the molecules that make up the organism.C) the science that seeks to understand what the universe does by studying interactions of molecules with atoms.D) the science that seeks to understand the interactions of molecules for the sake of advancing human control over nature.E) none of the above

52) Which statement about a hypothesis is TRUE?

A) It is a tentative interpretation or explanation.B) It has the potential to be proven wrong.C) It can be tested by experiments.D) It is part of the scientific method.E) All of the above statements are true.

53) How many significant digits should be reported in the answer to the following calculation? (4.3 - 3.7) × 12.3 =A) 1B) 2C) 3D) 4E) none of the above

54) Determine the answer for the equation below with correct number of significant figures: 3.215 × 13.2 ÷ 0.218 = ________ A) 194.669B) 195C) 194.7D) 194.67E) none of the above

55) An object weighing 1.840 kg has a volume of 0.0015 m3. What is the density of the object in g/cm3?


56) A lead ball has a mass of 55.0 grams and a density of 11.4 g/cm3. What is the volume of the ball?

A) 0.207 mLB) 0.207 LC) 4.82 mLD) 4.82 LE) none of the above

57) Which of the following items is a pure substance?A) airB) seawaterC) brassD) iceE) none of the above

58) When methane is burned with oxygen the products are carbon dioxide and water. If you produce 36 grams of water and 44 grams of carbon dioxide from 16 grams of methane, how many grams of oxygen were needed for the reaction?A) 32B) 80C) 96

D) 64E) none of the above

59) An energy diagram that shows the reactants having greater energy than the products illustrates an:A) endothermic reaction.B) exothermic reaction.C) isothermic reaction.D) impossible reaction.E) none of the above

60) Melting point can be defined as the temperature when a solid becomes a liquid. The melting point of the chemical acetone is -95°C. Which state of matter would you expect to exist for acetone at a temperature of -94°C?A) solidB) liquidC) gasD) plasma

61) When 49.5 J of heat was transferred to 7.3 g iron at 22°C, the temperature of iron increases to 37°C. What is the specific heat of iron in J/g∙°C?A) 4.5B) 0.45C) 2.2D) 24E) none of the above

62) Suppose it took 108 joules of energy to raise a bar of gold from 25.0°C to 29.7°C. Given that the specific heat capacity of gold is , what is the mass (in grams) of the bar of gold?

A) 6.5 × 101 g

B) 1.8 × 102 g

C) 1.28 × 102 g

D) 1.08 × 102 g


63) An atom containing 7 protons, 8 neutrons, and 7 electrons:A) is charge-neutral.B) is an ion.C) is an oxygen atom.D) cannot exist.E) none of the above

64) Which of the following is NOT a correct name, symbol combination?A) beryllium, BeB) phosphorus, PC) iron, FeD) manganese, MgE) silicon, Si

65) Which of the following statements about ions is INCORRECT?A) Cations are positive ions and anions are negative ions.B) Cations are formed when an atom loses electrons.C) Anions are formed when an atom gains electrons.D) Cations always have the same number of protons as electrons.E) All statements are correct.66) What is the charge on the ion formed by aluminum?A) 5-B) 3-C) 13+D) 3+E) none of the above

67) An atom that has the same number of neutrons as Ba is:

A) Cs

B) Ba

C) La

D) XeE) none of the above

68) A fictional element has two naturally occurring isotopes with the natural abundances shown here:

ISOTOPE ABUNDANCE18 40.0%20 60.0%

Which statement is TRUE for this element?A) The atomic mass would be less than 18.B) The atomic mass would be closer to 18 than to 20.C) The atomic mass would be exactly 19.D) The atomic mass would be closer to 20 than to 18.E) The atomic mass would be greater than 20.

69) A fictional element named Nivadium is found to have three naturally occurring isotopes with the natural abundances shown here:

MASS (amu) ABUNDANCE 22.1760 45.00% 23.1847 45.00% 24.1934 10.00%

The calculated atomic mass of Nivadium is:A) 7.61 amuB) 22.83 amu

C) 23.18 amuD) 69.55 amuE) none of the above

70) What is the oxygen-to-sulfur mass ratio of sulfur dioxide?A) 0.5B) 1.0C) 2.0D) 16E) none of the above

71) Suppose an unknown compound XY has an X-to-Y mass ratio of 4.0. If decomposition of compound XY gives 12.0 grams of X, then how many grams of Y must form?A) 48.0 gramsB) 12.0 gramsC) 4.0 gramsD) 3.0 gramsE) none of the above

78) How many total atoms are in the formula Al2(CO3)3?

A) 8B) 9C) 12D) 14E) none of the above

79) Carbon monoxide is considered which of the following?A) atomic elementB) molecular elementC) molecular compoundD) ionic compoundE) none of the above

80) What is the name of Ca(NO3)2?

A) calcium dinitriteB) calcium nitrateC) calcium nitrideD) calcium nitriteE) none of the above

81) The formula for potassium chlorate is KClO3. The formula for magnesium chloride is MgCl2. What is the

formula for magnesium chlorate?

A) MgClO3

B) Mg2ClO3

C) Mg(ClO3)2

D) Mg2(ClO3)3


82) Which of the following compounds have the smallest formula mass?

A) CO2

B) SO2

C) NO2

D) SiO2

E) H2O

83) When water is heated, bubbles form in the water. Is this evidence of a chemical reaction? Why?A) No, boiling water is a physical change.B) Yes, the formation of a gas is evidence of a chemical reaction.C) No, the formation of gas bubbles is a secondary chemical reaction which is ignored.D) Yes, the formation of a gas is proof a new compound has been made.E) none of the above

84) When the equation, ___O2 + ___C5H12 → ___CO2 + ___H2O is balanced, the coefficient:

of O2 is:


85) What are the coefficients for the following reaction when it is properly balanced?

___potassium iodide + ___lead (II) acetate → ___lead (II) iodide +___potassium acetate

A) 2, 1, 1, 1B) 2, 1, 1, 2C) 3, 2, 2, 1D) 1, 1, 2, 2E) none of the above

86) When the equation __NO2 + __H2O + __O2 → __HNO3 is balanced, the coefficient of HNO3 is:


87) Sodium metal reacts with water to form aqueous sodium hydroxide and hydrogen gas. Which equation below best describes the balanced equation for this reaction?

A) Na + H2O → NaOH (aq) + H (g)

B) S + H2O → SOH (aq) + H (g)

C) Na + H2O → NaOH (aq) + H2 (g)

D) 2Na + 2H2O → 2NaOH (aq) + H2 (g)

E) 2Na + H2O → Na2OH (aq) + H (g)

88) What type of a reaction occurs when a hydrochloric acid solution is mixed with a sodium bicarbonate solution?A) precipitationB) acid-base neutralizationC) oxidation-reduction D) gas evolutionE) no reaction

89) Methane gas (CH4), on complete combustion in air, produces:

1. CO2

2. H2

3. H2O

A) 1 and 2 onlyB) 1 and 3 onlyC) 2 and 3 onlyD) All of 1 and 2 onlyE) None of

90) When the equation, ___O2 + ___C6 H14 → ___CO2 + ___H2O is balanced, the coefficient of O2 is:


91) How are wavelength and frequency of light related?A) Wavelength is one-half of the frequency.B) Wavelength is double the frequency.C) Wavelength increases as frequency increases.D) Wavelength increases as the frequency decreases.E) Wavelength is independent of frequency.

92) What is the correct order of the electromagnetic spectrum from shortest wavelength to longest?A) Gamma Rays→X-rays→Ultraviolet Radiation→Visible Light→Infrared Radiation→Microwaves→Radio

WavesB) Visible Light→Infrared Radiation→Microwaves→Radio Waves→Gamma Rays→X-rays→Ultraviolet RadiationC) Radio Waves→X-rays→Ultraviolet Radiation→Visible Light→Infrared Radiation→Microwaves→Gamma RaysD) Gamma Rays→X-rays→Visible Light→Ultraviolet Radiation→Infrared Radiation→Microwaves→Radio WavesE) Gamma Rays→X-rays→Infrared Radiation→Visible Light→Ultraviolet Radiation→Microwaves→Radio Waves

93) The subshell letter:A) specifies the 3-D shape of the orbital.B) specifies the principal quantum number of the orbital.C) specifies the maximum number of electrons.D) specifies the principal shell of the orbital.E) none of the above

94) The n = ________ principal shell is the lowest that may contain a d-subshell.A) 1B) 2C) 3D) 4E) not enough information

95) Which statement is NOT true about "p" orbitals?A) A subshell contains three "p" orbitals.B) These orbitals are shaped like dumbbells.C) A 3p orbital has a higher energy than a 2p orbital.D) All three of these statements are true.E) none of the above

96) The subshell that has five orbitals and can hold up to ten electrons is the: A) d subshellB) f subshellC) s subshellD) p subshellE) none of the above

97) What do the alkali metals all have in common?A) They all undergo similar reactions.B) They all have similar physical properties.C) They all form +1 ions.D) They all have the same number of valence electrons.E) all of the above

98) If the electron configuration of a ground state potassium atom is 1s22s22p63s1, the electron configuration of the

potassium cation (K+) would be:

A) 1s22s22p63s2

B) 1s22s22p6

C) 1s22s22p63s1

D) 1s12s22p63s1


99) Which of the following atoms is the smallest?A) LiB) BeC) BD) OE) Ne

100) Which of the following statements about the mole is FALSE?A) One mole of atoms makes up an amount of atoms that can be seen with the naked eye.B) A mole of a monatomic element corresponds to one Avogadro's number of atoms.C) One mole of a monatomic element has a mass equal to its atomic mass expressed in grams.D) One mole of water contains 1/2 mole of oxygen atoms.E) none of the above

101) What is the mass in grams of 5.40 moles of lithium?A) 6.94B) 37.5C) 1.29

D) 3.25 × 1024


102) What is the molar mass of aluminum sulfate?A) 123.0 g/molB) 278.0 g/molC) 306.2 g/molD) 315.2 g/molE) 342.2 g/mol

103) One mole of (NH4)2HPO4 contains how many moles of hydrogen atoms?


104) What is the mass percent of chlorine in hydrochloric acid?A) 2.8B) 35.5C) 97.2D) 70.1


105) The simplest formula for hydrogen peroxide is HO. To determine its molecular formula, it is necessary to know: A) the properties of hydrogen peroxide.B) the density of hydrogen peroxide.C) the molar mass of hydrogen peroxide.D) the number of moles of hydrogen peroxide in 1.00 g of the substance.E) none of the above

106) Determine the empirical formula of a compound containing 60.3% magnesium and 39.7% oxygen.A) MgO

B) MgO2

C) Mg2O3

D) Mg2O


107) Vitamin C is known chemically by the name ascorbic acid. Determine the empirical formula of ascorbic acid if it is composed of 40.92% carbon, 4.58% hydrogen, and 54.50% oxygen.A) CHO

B) CH2O

C) C2H3O2

D) C3H4O3


108) A compound composed of only carbon and hydrogen is 25.2% hydrogen by mass. The empirical formula for this compound is:

A) CH 0.25

B) C3H

C) CH4

D) C2H8


109) What is the value of n when the empirical formula is C3H5 and the molecular mass is ?

A) 0.02B) 5C) 10D) 140E) none of the above

110) 1 torr is equal to:A) 760 mm Hg.B) 1 mm Hg.C) 1 Pa.D) 14.7 psi.E) all of the above

111) To solve problems using Boyle's Law, which mathematical equation should be used?

A) =

B) =

C) =

D) =


112) If the volume of a gas container at 32.0°C changes from 1.55 L to 755 mL, what will the final temperature be?A) 149°CB) 353°CC) 273°CD) -124°CE) none of the above

113) A sample of helium gas initially at 37.0°C, 785 torr and was heated to 58.0°C while the volume expanded to . What is the final pressure in atm?A) 517B) 0.681C) 1.79D) 3.21E) none of the above

114) The vapor pressure of water at 20.0°C is . If the pressure of a gas collected over water was measured to be . What is the pressure of the pure gas?A) 0.0230 atmB) 0.619 atmC) 0.573 atmD) 0.596 atmE) none of the above

115) Water can be formed according to the equation:

2H2 (g) + O2 (g) → 2H2O (g)

If 8.0 L of hydrogen is reacted at STP, exactly how many liters of oxygen at STP would be needed to allow complete reaction?A) 4.0 LB) 2.0 L

C) 1.0 LD) 8.0 LE) none of the above

116) Which statement about boiling point is FALSE?A) The boiling point is higher for compounds with strong intermolecular forces.B) The boiling point is higher for compounds with a high viscosity.C) The boiling point of a compound is an absolute constant.D) The boiling point of a compound is higher for nonvolatile compounds.E) All of the above statements are true.

117) The rate of vaporization of a liquid can be increased by:1. increasing the surface area2. increasing the temperature3. increasing the strength of the intermolecular forces

A) 1 onlyB) 2 onlyC) 3 onlyD) 1 and 2 onlyE) 2 and 3 only

118) Which substance below has dipole-dipole forces?

A) CH4

B) CO2

C) F2

D) H2S


119) Which intermolecular force is common to all polar molecules but NOT nonpolar molecules?A) dispersion forcesB) dipole-dipole forcesC) hydrogen bondingD) X-forcesE) none of the above

120) Which intermolecular forces are found in CO2?

A) dispersion forcesB) dipole-dipole forcesC) hydrogen bondingD) dispersion forces and dipole-dipole forcesE) none of the above

121) Suppose a vodka martini contains 30% alcohol with the remaining portion of the drink composed of water. What is the solute in this type of martini?A) waterB) alcohol

C) iceD) oliveE) none of the above

122) Which of the following compounds is a strong electrolyte?

A)

B)

C)

D) Na

E) all of the above

123) We dissolve 2.45 g of sugar in 200.0 g water. What is the mass percent of sugar in the solution?A) 1.21%B) 1.23%C) 2.42%D) 123%E) none of the above

124) What is the mass percent of a sodium fluoride solution prepared by dissolving of sodium fluoride into of water?A) 26.9%B) 42.3%C) 70.3%D) 29.7%E) none of the above

125) What is the molarity of a solution prepared by dissolving NaI in ?A) 42.8B) 0.0714

C) 2.86

D) 0.286E) none of the above

126) How many grams of KCl are needed to make of KCl?A) 9.13B) 1.52C) 91.3D) 0.123E) none of the above

127) What are the ion concentrations in a 0.12 M solution of AlCl3?

A) 0.36 M Al3+ ions and 0.12 M Cl- ions

B) 0.12 M Al3+ ions and 0.040 M Cl- ions

C) 0.12 M Al3+ ions and 0.36 M Cl- ions

D) 0.040 M Al3+ ions and 0.040 M Cl- ions


128) How many mL of 0.218 M sodium sulfate react with exactly of BaC given the reaction:

Ba (aq) + N S (aq) → BaS (s) + 2NaCl (aq)


129) Calculate the molarity of a KCl solution made by dissolving 24.7 g of KCl in a total volume of .A) 0.331B) 0.663C) 0.166D) 6.04E) none of the above

130) What is the conjugate acid of OH⁻?

A)

B) O

C) NaOHD) OH⁻E) none of the above

131) A 35.0 mL sample of 0.225 M HBr was titrated with 42.3 mL of KOH. What is the concentration of the KOH?A) 0.157 MB) 0.303 MC) 0.272 MD) 0.186 ME) none of the above

132) A 0.10 M solution of an electrolyte has a pH of 4.5. The electrolyte is:A) a strong acid.B) a strong base.C) a weak acid.D) a weak base.E) none of the above

133) A solution at 25°C has a hydrogen ion concentration of 2.6 × 10-5 M. Which of the following is TRUE?

A) [H3O+] > [OH-]

B) [H3O+] < [OH-]

C) [H3O+] = [OH-]

D) [H3O+] =

E) none of the above134) Which combination below will be a buffer solution? A) HCl and Cl⁻B) HNO3 and NaNO3

C) H and Na

D) NaBr and NaOHE) All of the above are true.

135) A buffer solution is all of the following EXCEPT:A) a solution that resists a change in pH when a base is added.B) a solution that resists a change in pH when an acid is added.C) a solution that contains both a weak acid and its conjugate base.D) a solution that regulates pH because it is such a strong acid or base.E) All of the above are true.

136) What is the [H⁺] in a solution that has a pH of 3.35?

A) 1 × M

B) 2.2 × M

C) 4.5 × M

D) 3.35 × M


137) A chemical equilibrium exists when:A) reactants are completely changed to products.B) there are equal amounts of reactants and products.C) the rate at which reactants form products becomes zero.D) the sum of reactant and product concentrations equals one mole.E) the rate at which reactants form products is the same as the rate at which products form reactants.

138) For the reaction ⇌ 2S + , the equilibrium expression is:

A) =

B) =

C) =

D) =


140) For the reaction 2 H2O (l) ⇌ 2H2 (g) + O2 (g), the equilibrium expression is:

A) = [H2O]2

B) = [H2]2 [O2]

C) =

D) = E) none of the above

141) Which of the following equilibrium systems will shift to the right (towards products) when pressure is increased.

A) 2 PbS (s) + 3O2 (g)⇌ 2PbO (s) + 2 SO2 (g)

B) PCl5 (g) ⇌ PCl3 (g) + Cl2 (g)

C) H2 (g) + CO2 (g)⇌ O (g) + CO (g)

D) all of theseE) none of these

142) For the reaction 2 O(g) ⇌ (g) + 2 (g), what happens to the equilibrium position if the pressure

decreases?A) shifts to the leftB) shifts to the rightC) does nothingD) doublesE) halves

143) Which compound below is the most soluble in water based on its value?

A) CuS, = 1.27

B) PbS, = 9.04

C) AgCl, = 1.77

D) AgI, = 8.51

E) not enough information

144) Which statement below is FALSE?A) The rate of a reaction can be increased by increasing concentrations of reactants.B) The rate of a reaction can be increased by altering the temperature.C) The rate of a reaction can be increased by adding a catalyst.D) A catalyst alters the equilibrium constant.E) All of the above are true.

145) Calculate the equilibrium constant (Keq) for the reaction 1A (aq) + 1B (aq) ⇌ 2C (aq) given that and at equilibrium.

A) 9.9B) 0.40

C) 2.5D) 20.


True/False Questions

1) TRUE2) FALSE3) FALSE4) FALSE5) TRUE6) FALSE7) FALSE8) FALSE9) FALSE10) FALSE

11) TRUE12) FALSE13) FALSE14) TRUE15) FALSE16) FALSE17) FALSE18) TRUE19) TRUE20) TRUE

21) FALSE22) FALSE23) TRUE24) FALSE25) FALSE26) TRUE27) TRUE28) TRUE29) TRUE30) FALSE

31) FALSE32) TRUE33) TRUE34) TRUE35) TRUE36) FALSE37) FALSE38) FALSE39) TRUE40) FALSE

41) TRUE42) TRUE43) FALSE44) TRUE45) TRUE46) TRUE47) TRUE48) FALSE49) TRUE50) TRUE

Multiple Choice Questions

1) B2) D3) C4) C5) A6) C7) B8) D9) A10) A11) B12) C13) C14) C15) B16) B17) D

18) B19) D20) D21) D22) D23) A24) D25) A26) D27) C28) D29) D30) D31) D32) C33) B34) D

35) D36) E37) D38) B39) C40) D41) A42) D43) D44) A45) D46) C47) B48) C49) A50) C51) E

53) A54) B55) A56) C57) D58) D59) B60) B61) B62) B63) A64) D65) D66) D67) D68) D69) B

70) B71) D78) D79) C80) B81) C82) E83) A84) D85) B86) C87) D88) D89) B90) C91) D92) A

93) A94) C95) D96) A97) E98) B99) E100) D101) B102) E103) D104) C105) C106) A107) D108) C109) B

110) B111) B112) D113) B114) C115) A116) C117) D118) D119) B120) A121) B122) D123) A124) D125) D126) A127) C128) A129) B130) B131) D132) C133) A134) C135) D136) C137) E138) B140) B141) A142) B143) C144) D145) C

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