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1. Which form of electromagnetic radiation has the longest wavelengths? A) gamma

ID: 1068987 • Letter: 1

Question

1. Which form of electromagnetic radiation has the longest wavelengths?

A) gamma rays

B) microwaves

C) radio waves

D) infrared radiation

E) x-rays

2. Which of the following frequencies corresponds to light with the longest wavelength?

A) 3.00 ´ 1013 s–1

B) 4.12 ´ 105 s–1

C) 8.50 ´ 1020 s–1

D) 9.12 ´ 1012 s–1

E) 3.20 ´ 109 s–1              

3. What is the wavelength of a photon of red light (in nm) whose frequency is 4.55 ´ 1014 Hz?

A) 659 nm

B) 1.52 ´ 106 nm

C) 152 nm

D) 455 nm

E) none of these              

4. How many electrons can be contained in all of the orbitals with n = 4?

A) 2

B) 8

C) 10

D) 18

E) 32

5. The electron configuration for the barium atom is:

A) 1s22s22p63s23p64s23d10

B) [Xe]6s2

C) 1s22s22p63s23p64s1

D) 1s22s22p63s23p64s2

E) none of these              

6. The electron configuration for the carbon atom is:

A) 1s22s22p2

B) [He]2s4

C) [Ne]2s22p2

D) 1s22p4

E) none of these

7. Which of the following processes represents the ionization energy of bromine?

A) Br(s) mc007-1.jpg Br+(g) + e–

B) Br(l) mc007-2.jpg Br+(g) + e–

C) Br(g) mc007-3.jpg Br+(g) + e–

D) Br(s) mc007-4.jpg Br+(s) + e–

E) Br2(g) mc007-5.jpg Br2+(g) + e–          

8. Order the elements S, Cl, and F in terms of increasing ionization energy.

A) S, Cl, F

B) Cl, F, S

C) F, S, Cl

D) F, Cl, S

E) S, F, Cl            

9. Atoms having equal or nearly equal electronegativity’s are expected to form

A) no bonds

B) polar covalent bonds

C) nonpolar covalent bonds

D) ionic bonds

E) covalent bonds           

10. Which of the following bonds is least polar?

A) C—O

B) H—C

C) S—Cl

D) Br—Br

E) They are all nonpolar.

11. In which case is the bond polarity incorrect?

A) d+H–Fd–

B) d+K–Od–

C) d+Mg–Hd–

D) d+Cl–Id–

E) d+Si–Sd–        

12. Which of these is an isoelectronic series?

A) Na+, K+, Rb+, Cs+

B) K+, Ca2+, Ar, S2–

C) Na+, Mg2+, S2–, Cl–

D) Li, Be, B, C

E) none of these (A-D)

13. Which of the following has the smallest radius?

A) F–

B) Ne

C) O2–

D) Mg2+

E) Na+

14. Calculate the lattice energy for LiCl(s) given the following:

sublimation energy for Li(s)        

+166 kJ/mol

DHf for Cl(g)      

+119 kJ/mol

first ionization energy of Li(g)     

+520. kJ/mol

electron affinity of Cl(g)

–349 kJ/mol

enthalpy of formation of LiCl(s)

–409 kJ/mol

A) 47 kJ/mol

B) 171 kJ/mol

C) –580 kJ/mol

D) –865 kJ/mol

E) none of these

Using the following electronegativity values:       

C             2.5                       Cl            3.0        

H            2.1                       O            3.5

select from the following group the molecule that fits the given statement:

a) CH3CHO

b) CO2

c) CH3Cl

d) C2H6

e) none

15. This molecule shows the smallest number of lone pairs in its Lewis structure.

A) CH3CHO

B) CO2

C) CH3Cl

D) C2H6

E) All have zero lone pairs.

16. Which of the following has an incomplete octet in its Lewis structure?

A) SO2

B) ICl

C) CO2

D) F2

E) NO

17. Which of the following exhibits resonance?

A) NH3

B) PCl5

C) H2O

D) O3

E) At least two of the molecules (A-D) exhibit resonance.              

18. In the molecule C2H4 the valence orbitals of the carbon atoms are assumed to be

A) not hybridized

B) sp hybridized

C) sp2 hybridized

D) sp3 hybridized

E) dsp hybridized             

19. Atoms that are sp2 hybridized form ____ pi bond(s).

A) 0

B) 1

C) 2

D) 3

E) 4

20. Consider the molecule:

               mc020-1.jpg

Specify the hybridization of each carbon atom.

               C-1         C-2         C-3         C-4         C-5

A) sp2          sp2          sp2          sp3          sp

B) sp2          sp2          sp2          sp3          sp3

C) sp2          sp2          sp3          sp3          sp2

D) sp2          sp2          sp3          sp3          sp3

E) sp2          sp           sp            sp2          sp

Explanation / Answer

1) Waves in the electromagnetic spectrum vary in size from very long radio waves the size of buildings, to very short gamma-rays smaller than the size of the nucleus of an atom.

2) 4.12x105 s-1

lemda= c / u { lemda = wavelength, c = speed of light, u = frequency}

3) lemda = (3.0x108 m/s / 4.55x1014Hz)

wavelength = 6.59x10-6 m = 659 nm

4) n1 = 2 (1s)

n2=8 (2s,2p)

n3= 18 (3s,3p,3d)

n4 = 32 electron (4s,4p,4d,4f)

5) barium atomic no. 56 = [Xe]6s2

6)carbon atom atomic no. = 6

1s2,2s2,2p2

8) S < Cl <F