name: chemistry regents august 2015 - … chemistry regents august 2015 a) ... 10.based on table s,...

Name: Chemistry Regents August 2015

A) electron-positive, neutron-negative,proton-neutral

B) electron-negative, neutron-neutral,proton-positive

C) electron-negative, neutron-positive,proton-neutral

D) electron-neutral, neutron-positive,proton-negative

1. Which subatomic particles are paired with theircharges?

A) Cr B) Cu C) Ni D) Se

2. In the ground state, an atom of which element has twovalence electrons?

A) absorb energyB) absorb positrons

C) emit energyD) emit positrons

3. The atoms in a sample of an element are in excitedstates. A bright-line spectrum is produced when theseatoms

A) Positrons are located in shells outside thenucleus.

B) Neutrons are located in shells outside thenucleus.

C) Protons are located in orbitals outside thenucleus.

D) Electrons are located in orbitals outside thenucleus.

4. Which statement describes a concept included in thewave-mechanical model of the atom?

A) atomic massB) molar massC) number of neutrons per atomD) number of protons per atom

5. All elements on the modern Periodic Table arearranged in order of increasing

A) ammoniaB) chlorine

C) neonD) nitrogen

6. At STP, which substance is a noble gas?

A) different molecular structures and differentproperties

B) different molecular structures and the sameproperties

C) the same molecular structure and differentproperties

D) the same molecular structure and the sameproperties

7. At STP, oxygen exists in two forms, and . These two forms of oxygen have

A) Sodium has a melting point of 371 K.B) Sodium has a molar mass of 23 grams.C) Sodium can conduct electricity in the liquid

phase.D) Sodium can combine with chlorine to produce a

salt.

8. Which statement describes a chemical property ofsodium?

A) decompositionB) distillation

C) sublimationD) vaporization

9. Which term identifies a type of chemical reaction?

A) poloniumB) sulfur

C) seleniumD) tellurium

10. Based on Table S, an atom of which element has the weakest attraction for electrons in achemical bond?

A) Energy is absorbed as a bond is formed.B) Energy is absorbed as a bond is broken.C) Energy is released as a bond is formed.D) Energy is released as a bond is broken.

11. Given the balanced equation:

Which statement describes what occurs during thisreaction?

A) O and SeB) O and Sr

C) O and HD) O and P

12. Which atoms will bond when valence electrons aretransferred from one atom to the other?

A)B)

C)D)

13. Which sample of matter is a mixture?

A) increase the energy content of the gas sampleB) produce strong attractive forces between the

gas particlesC) result in a net loss of energy by the gas sampleD) transfer energy between the gas particles

14. According to kinetic molecular theory, collisionsbetween gas particles in a sample of an ideal gas

A) ethaneB) propanone

C) siliconD) water

15. Which substance can not be broken down by achemical change?

A) average potential energy of the particles of thesample

B) average kinetic energy of the particles of thesample

C) total nuclear energy of the sampleD) total thermal energy of the sample

16. The temperature of a sample of matter is a measureof the

A) 37 K and 1 atmB) 37 K and 8 atm

C) 347 K and 1 atmD) 347 K and 8 atm

17. Under which conditions of temperature and pressuredoes a real gas behave most like an ideal gas?

A) a compoundB) an element

C) a mixtureD) a substance

18. The ratio of chromium to iron to carbon variesamong the different types of stainless steel.Therefore, stainless steel is classified as

A) The reacting particles have less energy andcollide less frequently.

B) The reacting particles have less energy andcollide more frequently.

C) The reacting particles have more energy andcollide less frequently.

D) The reacting particles have more energy andcollide more frequently.

19. Which statement explains why increasing thetemperature increases the rate of a chemicalreaction, while other conditions remain the same?

A) more water is added to the flaskB) the flask is stopperedC) the temperature is decreased to 15°CD) the temperature is increased to 35°C

20. An open flask is half filled with water at 25°C. Phaseequilibrium can be reached after

A)B)

C)D)

21. Which formula represents an unsaturated organiccompound?

A) molecular formulaB) structural formulaC) physical propertiesD) IUPAC name

22. All isomers of octane have the same

A)B)

C)D)

23. Which formula represents a hydrocarbon?

A) protons lostB) neutrons lost

C) neutrons gainedD) electrons gained

24. In a redox reaction, the number of electrons lost isequal to the number of

A) the anode in a voltaic cell and the cathode in anelectrolytic cell

B) the cathode in a voltaic cell and the anode in anelectrolytic cell

C) the anode in both a voltaic cell and anelectrolytic cell

D) the cathode in both a voltaic cell and anelectrolytic cell

25. At which electrode does oxidation occur in a voltaiccell and in an electrolytic cell?

A)B)

C)D)

26. Based on the Arrhenius theory, when potassiumhydroxide dissolves in water, the only negativeion in the aqueous solution is

A) better electrical conductivityB) poorer electrical conductivityC) a lower boiling point at standard pressureD) a higher freezing point at standard pressure

27. Compared to distilled water, an aqueous salt solutionhas

A) donate an ionB) accept an ion

C) donate an ionD) accept an ion

28. According to one acid-base theory, water can act asa base because a water molecule can

A) a longer half-life and the same decay modeB) a longer half-life and a different decay modeC) a shorter half-life and the same decay modeD) a shorter half-life and a different decay mode

29. Compared to the half-life and decay mode of thenuclide , the nuclide has

A) Ionic bonds are broken.B) Ionic bonds are formed.C) Energy is converted to mass.D) Mass is converted to energy.

30. Which net change occurs in a nuclear fusionreaction?

A) An atom is electrically neutral.B) An atom is mostly empty space.C) The nucleus of an atom is negatively charged.D) The electrons in an atom are located in specific

shells.

31. Which conclusion was drawn from the results of thegold foil experiment?

A) 2-7-3 B) 2-7-6 C) 2-8-2 D) 2-8-5

32. Which electron configuration represents an atom ofmagnesium in an excited state?

A) Group 1B) Group 2

C) Group 17D) Group 18

33. Which group on the Periodic Table has elementswith atoms that tend not to bond with atoms of otherelements?

A) 1 B) 2 C) 17 D) 18

34. Which group on the Periodic Table has at least oneelement in each of the three phases ofmatter at STP?

A) one electron in the outermost shellB) two electrons in the outermost shellC) one neutron in the nucleusD) two neutrons in the nucleus

35. Rubidium and cesium have similar chemicalproperties because, in the ground state, the atoms ofboth elements each have

A) decreasesB) increasesC) decreases, then increasesD) increases, then decreases

36. As the first five elements in Group 15 are consideredin order of increasing atomic number, first ionizationenergy

A) HF B) HCl C) HBr D) HI

37. Which substance in the table below has the strongest intermolecular forces?

A) B) C) D)

38. Which ion in the ground state has the same electronconfiguration as an atom of argon in theground state?

A) 1 B) 2 C) 3 D) 6

39. What is the number of pairs of electrons shared in amolecule of ?

A) At STP, carbon has a greater density thanfluorine.

B) A carbon atom has more valence electrons thana fluorine atom.

C) The difference in electronegativity betweencarbon and oxygen is greater than that betweenfluorine and oxygen.

D) The difference in first ionization energybetween carbon and oxygen is greater than thatbetween fluorine and oxygen.

40. Which statement explains why a C-O bond is morepolar than a F-O bond?

A) Evaporate the water, then filter out the salt.B) Evaporate the water, then filter out the sand.C) Filter out the salt, then evaporate the water.D) Filter out the sand, then evaporate the water.

41. A mixture consists of sand and an aqueous saltsolution. Which procedure can be used to separatethe sand, salt, and water from each other?

A) 4.3 ppmB) 8.5 ppm

C) 17 ppmD) 34 ppm

42. An aqueous solution has a mass of 490 gramscontaining gram of calcium ions. Theconcentration of calcium ions in this solution is

A) 1.0 atmB) 2.0 atm

C) 3.0 atmD) 4.0 atm

43. A sample of hydrogen gas at 2.0 atmospheres and273 K occupies a volume of 5.0 liters. The gassample is completely transferred to a 10.0-litersealed, rigid container. What is the new pressure ofthe gas sample when the temperature returns to 273K?

A) increasesB) remains the sameC) increasesD) remains the same

44. Given the equation for a system at equilibrium:

If only the concentration of is increased, theconcentration of

A) 3-heptyneB) 4-heptyne

C) 3-hepteneD) 4-heptene

45. A hydrocarbon molecule has seven carbon atoms ina straight chain. There is a double bondbetween the third carbon atom and the fourth carbonatom in the chain. The IUPAC name forthis hydrocarbon is

A) additionB) fermentation

C) polymerizationD) substitution

46. Given the balanced equation representing a reaction:

Which type of reaction is represented by thisequation?

A) each otherB) a battery

C) a switchD) a voltmeter

47. Given the diagram representing an incompleteelectrochemical cell:

Solid copper will be deposited on one of the carbonelectrodes when the wires are connected to

A) 3.6 mLB) 5.6 mL

C) 20. mLD) 40. mL

48. What is the volume of neededto completely neutralize 15.0 milliliters of

?

A)B)C)D)

49. Which equation represents a spontaneoustransmutation?

A) B) C) D)

50. Which particle has two neutrons?

51. Determine the vapor pressure of ethanol at .

52. Explain, in terms of particle arrangement, why a sample of solid NaCl has less entropy than a sampleof aqueous NaCl.

53. Determine the molecular formula for a compound that has the empirical formula and a molarmass of 120. grams per mole.

54. A student drew the Lewis electron-dot diagram below to represent sodium chloride .

Explain why this diagram is not an accurate representation for the bonding in NaCl

55. Given the formula for heptanal:

Determine the gram-formula mass of heptanal.

56. Compare the mass of a proton to the mass of an electron.

57. In nature, 1.07% of the atoms in a carbon sample are C-13 atoms. show a numerical setup forcalculating the number of C-13 atoms in a sample containing atoms of carbon.

Base your answers to questions 58 and 59 on the information below and on your knowledge ofchemistry.

A sample of a substance is a liquid at 65°C. The sample is heated uniformly to 125°C. Theheating curve for the sample at standard pressure is shown below.

58. Determine the boiling point of the sample at standard pressure.

59. State what happens to the potential energy of the particles of the sample during time interval BC.

Base your answers to questions 60 and 61 on information below and on your knowledge of chemistry.

A sample of nitric acid contains both ions and ions. This sample has a pH value of1.

60. Write a name of the positive ion present in this sample.

61. What is the color of methyl orange after it is added to this sample?

Base your answers to questions 62 through 65 on the information below and on your knowledge ofchemistry.

One fission reaction for U-235 is represented by the balanced nuclear equation below.

Both radioisotopes produced by this fission reaction undergo beta decay. The half-life ofXe-140 is 13.6 seconds and the half-life of Sr-94 is 1.25 minutes.

62. Explain, in terms of both reactants and products, why the reaction represented by the nuclearequation is a fission reaction.

63. Complete the equation below for the decay of Xe-140 by writing a notation for the missing product.

64. Determine the time required for an original 24.0-gram sample of Sr-94 to decay until only 1.5 gramsof the sample remains unchanged.

65. On the diagram, draw an arrow to represent the path of an emitted beta particle in the electric fieldbetween two oppositely charged metal plates.

Base your answers to questions 66 through 68 on information below and on your knowledge ofchemistry.

The two naturally occurring isotopes of antimony are Sb-121 and Sb-123. The table belowshows the atomic mass and percent natural abundance for these isotopes.

Antimony and sulfur are both found in the mineral stibnite, . To obtain antimony,stibnite is roasted (heated in air), producing oxides of antimony and sulfur. The unbalancedequation below represents one of the reactions that occurs during the roasting.

66. Determine the percent composition by mass of antimony in stibnite (gram-formula mass = 340.g/mol).

67. Show a correct numerical setup for calculating the atomic mass of antimony.

68. Complete the balancing of the equation below for the roasting of stibnite, using the smallestwhole-number coefficients.


In a laboratory investigation, ammonium chloride was dissolved in water. Laboratoryprocedures and corresponding observations made by a student during the investigation are shownin the table below.

69. Identify two types of bonds in the solute.

70. State evidence from the investigation that indicates the solution is saturated.

71. State evidence from the investigation that indicates the process of dissolving the in wateris endothermic.

72. State the observation that would be made if procedure 3 is repeated with the original temperature ofthe at 98°C.


Coal is a fuel consisting primarily of carbon. In an open system, the carbon that bumscompletely in air produces carbon dioxide and heat. This reaction is represented by the balancedequation below.

73. Use the key to draw at least five particles in the box to represent the phase of the product.

74. On the potential energy, draw a double-headed arrow to indicate the interval that represents theheat of reaction.


During the winter months, icy roads pose a threat to motorists and can lead to accidents. Amixture of sand and sodium chloride, NaCl, can be spread on roads to make winter driving safer. One New York town requires that a mixture of sand and salt used on residential roads shouldcontain 25% or less of NaCl by mass. A 10.0-gram sample of a mixture of sand and Na Cl wasanalyzed and found to contain 3.3 grams of NaCl.

75. State, in terms of freezing point, why sodium chloride is part of the mixture put on icy roads.

76. Explain, in terms of composition by mass, why the mixture from which the analyzed sample wastaken should not be used on residential roads of the town.


In a laboratory investigation, a solution that contains 13.2 grams of reactscompletely with a solution that contains 12.0 grams of NaI, producing 18.4 grams of and anundetermined mass of a second product, . This reaction is represented by the balancedequation below.

77. Identify the compound produced that is insoluble in water.

78. Determine the mass of produced.


Two organic compounds, geraniol and linalool, can be represented by the molecular formula . Geraniol has an odor similar to the scent of roses and linalool has an odor similar to

the scent of citrus fruits. Both compounds are nearly insoluble in water. The structural formulas ofgeraniol and linalool are shown below.

79. Write the name of the class of organic compound to which both geraniol and linalool belong.

80. Explain, in terms of molecular polarity, why geraniol and linalool are nearly insoluble in water.


The gastric juice of the human stomach has a pH value of approximately 1.5. Hydrochloricacid in the gastric juice is necessary for the digestion process. However, excess hydrochloric acidmay harm the stomach lining. One type of antacid uses to neutralize excesshydrochloric acid in the stomach. This neutralization is represented by the incomplete equationbelow.

81. Complete the equation by writing the formula of the missing product.

82. Describe the changes in both the hydrogen ion concentration and the pH of the gastric juice of ahuman after ingesting this type of antacid.


Early scientists defined oxidation as a chemical reaction in which oxygen combined withanother element to produce an oxide of the element. An example of oxidation based on thisdefinition is the combustion of methane. This reaction is represented by the balanced equationbelow.

Equation 1:

The definition of oxidation has since been expanded to include many reactions that do notinvolve oxygen. An example of oxidation based on this expanded definition is the reactionbetween magnesium ribbon and powdered sulfur when heated in a crucible. This reaction isrepresented by the balanced equation below.

Equation 2: 83. State why early scientists classified the reaction represented by equation 1 as oxidation.

84. Determine the change in oxidation number of carbon in equation 1.

85. Write a balanced half-reaction equation for the oxidation that occurs in the reaction represented byequation 2.

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