Chem Exam #1

1. 1Select the correct description for O2 and O3. These two substances are :

   1. Aelements, molecules and isotopes
   2. Bcompounds, molecules, and isotopes
   3. Celements, molecules, and allotropes
   4. Dcompounds, molecules, and allotropes
   5. Emolecules, allotropes,and isotopes
2. 2How many protons, electrons, and neutrons are resent in ^36 S ^2-

   1. A16 protons, 16 electrons, 20 neutrons
   2. B16 protons, 18 electrons, 20 neutrons
   3. C16 protons,18 electrons, 36 neutrons
   4. D36 protons, 18 electrons, 16 neutrons
   5. E36 protons, 16 electrons, 20 neutrons
3. 3What key physical property was determined in Thomson's cathode ray experiment?

   1. Athe charge of a proton
   2. Bthe mass-to-charge ratio of a proton
   3. Cthe mass of an electron
   4. Dthe mass-to-charge ratio of an electron
   5. Ethe spin of an electron
4. 4If an electron moves closer to a nucleus, which of the following is true regarding the electron energy and its chemical reactivity:

   1. Aits energy increases and it becomes more reactive
   2. Bits energy increases and it becomes less reactive
   3. Cits energy decreases and it becomes more reactive
   4. Dits energy decreases and it becomes less reactive
5. 5If a sample of C16H27N4O3(Mm = 323 g/mol) contains 4.45g of nitrogen, what is the mass of the sample?

   1. A(4.45)(323) / (14)(4)
   2. B(4.45)(4)(323) / (14)
   3. C(4.45)(4)(14) / (323)
   4. D(4.45)(14) / (323)(4)
   5. E(4.45)(1323) / (14)
6. 6Choose the correct setup. How many moles of hydrogen atoms are present in a 125 g samples of Ga(H2PO4)3? Molar mass of Ga(H2PO4)3 is 360.2 g/ mol.

   1. A(125)(360.2)(6.02 x 10^23) / (6)
   2. B(125)(6.02 x 10^23) / (360.2)(6)
   3. C(125)(6)(6.02 x 10^23) / (360.2)
   4. D(125)(6) / (360.2)
   5. E(125) / (360.2)(6)
7. 7Select the system of charged particles with the lowest electrostatic potential energy.

   1. A+3 and +4 charges separated by 2 nm
   2. B-2 and -8 charges separated by 4 nm
   3. C+1 and -2 charges separated by 1 nm
   4. D-3 and +2 charges separated by 6 nm
8. 8If you are comparing two beams of light of different frequency, one at 3 x 10^13 s^-1 and the other at 5 x 10^17 s^-1, which light will exhibit the longer wavelength, and which beam will be composed of higher energy photons?

   1. ALonger wavelength: 3 x 10^13 s^-1
      Higher energy: 3 x 10^13 s^-1
   2. BLonger wavelength: 3 x 10^13 s^-1
      Higher energy: 5 x 10^17 s^-1
   3. CLonger wavelength: 5 x 10^17 s^-1
      Higher energy: 3 x 10^13 s^-1
   4. DLonger wavelength: 5 x 10^17 s^-1
      Higher energy: 5 x 10^17 s^-1
9. 9According to the Bohr model for a 1-electron atomic species ( where Z = atomic number, and n= principal quantum number), the energy of the electron in the nth orbit is proportional to:

   1. A-Z^2/n^2
   2. B-n/Z^2
   3. C-n/Z
   4. D-n^2/Z^2
   5. E-Z^2/n
10. 10Compared to the photon that would be emitted as a result of the n=2 -> n=1 electron transition in the hydrogen atom, would the photon emitted in the 2-> 1 transition of the Li^2+ ion be of lower or higher energy?

    1. Alower
    2. Bhigher

11. 11Select the process involving particle interactions that would result in a decrease in energy.

    1. ATwo helium atoms move farther apart
    2. BA lithium ion moves farther away from a chloride ion
    3. CAn electron moves from the n=1 level to the n=2 level
    4. DAn electron moves farther away from a nucleus
    5. ETwo anions move farther away
12. 12In diagrams of p orbitals, what is the significance of the different colors or shadings given to the two lobes?

    

    1. AEach lobe holds a different electron
    2. BThe sign of the orbital wave function is positive in one lobe, negative in the other
    3. CThe spin quantum number is +1/2 in one lobe, -1/2 in the other.
    4. DThe magnetic quantum number +1 in the one lobe, -1 in the other
    5. EOne lobe carries negative charge whereas the other lobe carries positive charge.
13. 13For the p orbital shown in the preceding problem, which of the following sets of quantum numbers could be an acceptable set?

    1. An = 4, l = 2, ml = 2
    2. Bn = 2, l = 2, ml = 1
    3. Cn = 1, l = 1, ml = -1
    4. Dn = 3, l = 1, ml = 0
    5. En = 4, l = 0, ml = 0
14. 14How many nodal planes are present in a d orbital?

    1. A0
    2. B1
    3. C2
    4. D3
    5. E4
15. 15How many orbitals are present in the 5f sublevel

    1. A5
    2. B7
    3. C10
    4. D14
    5. E20
16. 16Shown is the electron energy diagram for the hydrogen atom reproduced from Chapter 2 of our textbook. Which of the following electronic transitions occurring in a hydrogen atom would require absorption of the highest energy photon?

    

    1. An = 8 -> n = 7
    2. Bn = 5 -> n = 2
    3. Cn = 2 -> n = 8
    4. Dn = 1 -> n = 2
    5. En = 1 -> n = 4
17. 17Of the transitions given in the preceding problem, which one would result in emission of the longest wavelength photon?

    

    1. An = 8 -> n = 7
    2. Bn = 5 -> n = 2
    3. Cn = 2 -> n = 8
    4. Dn = 1 -> n = 2
    5. En = 1 -> n = 4
18. 18Which two quantum numbers are predictive of the energy of an electron in an orbital?

    1. Aml and ms
    2. Bn and ml
    3. Cl and ml
    4. Dl and ms
    5. En and l
19. 19Which electron quantum number (QN) gives rise to the magnetic properties of atoms?

    1. Aprincipal QN (n)
    2. Bspin QN (ms)
    3. Cangular momentum QN (l)
    4. Dmagnetic QN (ml)
20. 20The electron configuration of lead is :

    1. A[Xe] 6s^2 4f^14 5d^10 6p^2
    2. B[Xe] 6s^2 6f^14 6d^10 6p^2
    3. C[Xe] 6s^2 6p^2
    4. D[Xe] 6s^2 5d^10 6p^2
    5. E[Xe] 6s^2 6d^10 6p^2
21. 21How many core electrons are present in a lead atom?

    1. A54
    2. B58
    3. C64
    4. D78
    5. E80

Description

Quiz on Chem Exam #1, created by cheetahgoddess on 05/12/2014.

Author

cheetahgoddess

Language

English

Views

7

Tags

chemistry

Rating

No ratings yet

Rate this quiz

Rate this quiz

More on Moles and Stoichiometry