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Practice Final Exam 2009
- Please fill in “A” for question 1 on your scantron sheet because you have Version A of the exam: (a) Fill in “A”
- 1.0250 has ___ significant figures.
(a) one (b) two (c) three (d) four (e) five
- Which of the following statements are true?
(a) For each element there is only one isotope. (b) The mass number for an element is equal to its number of protons. (c) For a neutral atom, the number of neutrons is equal to the number of electrons. (d) All of the above statements are false. (e) All of the above statements are true.
- An ionic compound forms when magnesium reacts with bromine. If a sample of the compound contains 1.0 × 10^22 magnesium ions, how many bromide ions does it contain? (a) 5.0 × 10^21 bromide ions (b) 1.0 × 10^22 bromide ions (c) 2.0 × 10^22 bromide ions (d) 3.0 × 10^22 bromide ions (e) 4.0 × 10^22 bromide ions
- The reaction of fluorine and hydrogen gases at high temperature produces hydrogen fluoride. If 20.0 g of fluorine reacts with 1.00 g of hydrogen, how much fluorine gas remains after the reaction? (a) 0.526 g fluorine gas (b) 1.15 g fluorine gas (c) 10.6 g fluorine gas (d) 19.8 g fluorine gas (e) None. All of the fluorine gas is consumed.
Practice Final Exam 2009
- If 10.0 g of sodium sulfate is dissolved in 500. mL of water, what is the concentration of sulfate ions? (a) 0.141 M sulfate ions (b) 0.168 M sulfate ions (c) 0.194 M sulfate ions (d) 0.282 M sulfate ions (e) 0.336 M sulfate ions
- List the following gases in order of increasing density, if temperature and pressure are constant.
(a) Ar < CO 2 < F 2 < NO 2 (b) NO 2 < CO 2 < F 2 < Ar (c) F 2 < CO 2 < NO 2 < Ar (d) F 2 < Ar < CO 2 < NO 2 (e) CO 2 < NO 2 < Ar < F 2
- A 25.0 g sample of xenon hexafluoride is confined in a 4.75-L vessel at 35.0 °C. What is the pressure? (a) 0.0616 atm (b) 0.542 atm (c) 0.616 atm (d) 1.37 atm (e) 5.42 atm
- Sand consists primarily of silicon dioxide and is a source of pure silicon for the electronics industry. If sand is heated with carbon, pure silicon and carbon monoxide are produced. How many grams of sand are required to produce 12.5 g of pure silicon if the reaction yield is only 85. %? (a) 31.5 g (b) 53.5 g (c) 23.1 g (d) 26.7 g (e) 62.9 g
- What is the effect of increasing the temperature by a factor of two AND increasing the pressure by a factor of two on an ideal gas, if the number of moles is held constant? (a) The volume does not change. (b) The volume increases by a factor of two. (c) The volume decreases by a factor of two. (d) The volume increases by a factor of four. (e) The volume decreases by a factor of four.
Practice Final Exam 2009
- What is the energy of one photon of microwave radiation with a frequency of 9.13 GHz?
(a) 6.05 10 -24^ J (b) 6.05 10 -33^ J (c) 2.18 10 -35^ J (d) 2.18 10 -26^ J (e) 2.18 10 -21^ J
- How many electrons can have the designation 4 d?
(a) one (b) two (c) three (d) six (e) ten
- Which of the following has the set of ions correctly arranged in order of increasing size (from smallest to largest). (a) As3-^ < Se2-^ < Br-^ < Rb+^ < Sr2+ (b) Sr 2+^ < Rb+^ < Br-^ < Se2-^ < As3- (c) As3-^ < Br-^ < Rb+^ < Se2-^ < Sr2+ (d) Br-^ < Rb+^ < Se2-^ < Sr2+^ < As3+ (e) As3+^ < Sr2+^ < Se2-^ < Rb+^ < Br-
- Which of the following has the set of atoms correctly arranged in order of increasing IE 1 (from smallest to largest) (a) Cs < Sr < Se < Cl < He (b) Cl < Cs < He < Se < Sr (c) He < Cl < Se < Sr < Cs (d) He < Cs < Sr < Se < Cl (e) Cl < Se < Sr < Cs < He
- In chemistry, the following partial orbital diagram represents:
(a) The ground state configuration of nitrogen. (b) The excited state configuration of nitrogen. (c) The ground state configuration of oxygen. (d) The excited state configuration of oxygen. (e) The ground state configuration of fluorine.
Practice Final Exam 2009
- When 50.0 mL of 2.00 M hydrochloric acid is added to 50.0 mL of 2.00 M sodium hydroxide in a calorimeter at 16.9 °C, the temperature rises to 30.4 °C. Determine the heat capacity of the calorimeter given that the density of the resulting sodium chloride solution is 1.04 g/mL and c = 3.93 J/g·K, and the balanced thermochemical equation below. NaOH( aq ) + HCl( aq ) → NaCl( aq ) + H 2 O( l ) Δ H rxn = –57.32 kJ (a) 3840 J/K (b) 833 J/K (c) 19.6 J/K (d) 15.7 J/K (e) 9.20 J/K
- Diamond and graphite are two crystalline forms of carbon. At 1 atm and 25 °C, diamond changes to graphite so slowly that the enthalpy change of the process must be obtained indirectly. Determine Δ H rxn for C( diamond ) → C( graphite ) With equations from the following list: C( diamond ) + O 2 ( g ) → CO 2 ( g ) Δ H rxn = –395.4 kJ 2CO 2 ( g ) → 2CO( g ) + O 2 ( g ) Δ H rxn = +566.0 kJ C( graphite ) + O 2 ( g ) → CO 2 ( g ) Δ H rxn = –393.5 kJ 2CO( g ) → C( graphite ) + CO 2 ( g ) Δ H rxn = –172.5 kJ (a) +1.9 kJ (b) –1.9 kJ (c) +3.9 kJ (d) –3.8 kJ (e) +170. kJ
- What is the wavelength of an electron ( m = 9.10939 10 -31^ kg) moving at one-half the speed of light? (a) 2.42 pm (b) 242 nm (c) 4.85 pm (d) 485 nm (e) 910 nm
- Which of the following statements is scientifically true?
(a) For a hydrogenic atom or ion, the energies of the orbitals depend only on the value of n. (b) For a many-electron atom, the energies of the orbitals depend on both n and l. (c) In a carbon atom, the 2 s orbital is at a lower energy than the 2 p orbitals. (d) The Bohr model works for the He+^ ion because it is a hydrogenic ion. (e) All of the above statements are true.
Practice Final Exam 2009
- What is the hybridization of the carbon atoms in the acetate ion CH 3 CO 2 −?
C
O C
O
H
H
H
(a) sp and sp^2 (b) sp^2 and sp^3 (c) both sp^3 (d) sp and sp^3 (e) both sp^2
- Which of the following statements are true?
(a) A double bond consists of two π bonds. (b) sp^3 hybrid orbitals can form π bonds. (c) A σ bond contains a node in the bonding overlap region. (d) All of the above statements are true. (e) None of the above statements are true.
- How would you classify the bonds in the oxalate anion C 2 O 4 2-^? It will be helpful to draw a Lewis structure. (a) 7 σ bonds (b) 6 σ bonds and 1 π bond (c) 5 σ bonds and 2 π bonds (d) 3 σ bonds and 2 π bonds (e) 4 σ bonds and 3 π bonds
Practice Final Exam 2009
- Which of the following has the set of molecules correctly arranged in order of increasing bond order? Use the molecular orbital diagram below to help answer this question.
(a) F 2 +^ < F 2 < F 2 − (b) F 2 −^ < F 2 < F 2 + (c) F 2 < F 2 +^ < F 2 − (d) F 2 −^ < F 2 +^ < F 2 (e) F 2 +^ < F 2 −^ < F 2
- Which of the following diatomic molecules has the highest boiling point?
(a) F 2 (b) Cl (^2) (c) Br 2 (d) I 2 (e) All of these molecules have the same boiling point.
- In which of the following substances would you expect hydrogen bonding forces to be important?
(a) NH 3 (b) CH (^4) (c) BH 3 (d) PCl (^3) (e) BCl 3
Practice Final Exam 2009
- Consider an element from Period 3 with the successive ionization energies given below. A sample of this element reacts with hydrogen gas to give a neutral molecule. What is the shape of this molecule? (All ionization energies are in kJ/mol) IE 1 = 999.6 IE 2 = 2252 IE 3 = 3357 IE 4 = 4556 IE 5 = 7004 IE 6 = 8496 IE 7 = 27107 IE 8 = 31719 IE 9 = 36621 IE 10 = 43177 (a) linear (b) trigonal planar (c) trigonal pyramidal (d) bent (e) tetrahedral
- We have found a sample of a mysterious substance X and the only information given to us was a phase diagram, shown below. From this phase diagram, which of the following statements are true?
(a) The density of solid X is greater than the density of liquid X. (b) It is possible at low temperatures to sublime X. (c) At temperature above point T, the solid phase cannot exist. (d) Both (a) and (b) are true. (e) Both (b) and (c) are true.
Practice Final Exam 2009
- You are given four sealed vials that each contain a different gas. The volume of the vials are equal and the pressure in each vial is 1 atm. The four gases are hydrogen, nitrogen, oxygen, and fluorine. If all of the vials are at the same temperature, which vial contains the greatest number of molecules? (a) hydrogen (b) nitrogen (c) oxygen (d) fluorine (e) All of the vials contain the same number of molecules.
