Chem 1021 - Final Exam Practice Questions

Greenlight has a wavelength of 520 nm while orangelight has a wavelength of 5.9 x 10-7m. Which light has the higher frequency? A. Green light B. Orange light C. They have the same frequency D. Need more information to answer this question.

A. Green light

When completing the electron configuration for the element phosphorus, which of the following statements is correct? A. There are five electrons in the third energy level. B. The 2p sublevel is not full. C. There are electrons in the 3d sublevel. D. There are no electrons in the 3s sublevel. E. There is one unpaired electron in the 3p sublevel.

A. There are five electrons in the third energy level.

Predict the molecular shape and give the approximate bond angles of the CO2 molecule. A. linear, 180o B. trigonal planar, 120o C. tetrahedral, 109.5o D. trigonal pyramidal, 109.5o E. bent, 120o

A. linear, 180o

Rank the following electron transitions in a hydrogen atom from shortest wavelength to longest wavelength: n = 5 to n = 2, n = 4 to n = 2, n = 6 to n = 2, n = 3 to n = 2 A. n = 6 to n = 2 < n = 5 to n = 2 < n = 4 to n = 2 < n = 3 to n = 2 B. n = 3 to n = 2 < n = 4 to n = 2 < n = 5 to n = 2 < n = 6 to n = 2 C. n = 5 to n = 2 < n = 4 to n = 2 < n = 6 to n = 2 < n = 3 to n = 2 D. n = 5 to n = 2 < n = 6 to n = 2 < n = 4 to n = 2 < n = 3 to n = 2 E. n = 6 to n = 2 < n = 4 to n = 2 < n = 5 to n = 2 < n = 3 to n = 2

A. n = 6 to n = 2 < n = 5 to n = 2 < n = 4 to n = 2 < n = 3 to n = 2

A laser used in DVD players has a wavelength of 405 nm. What is the energy of this light in joules? A. 4.91 × 10-28 J B. 4.91 × 10-19 J C. 8.05 × 10-32 J D. 8.05 × 10-23 J E. 2.98 × 10-48 J

B. 4.91 × 10-19 J

Which of the following transitions in the Bohrhydrogen atom leads to emission of a photon with the shortest wavelength? A. 1 6 B. 6 1 C. 6 3 D. 3 6

B. 6 1 Remember, and are inversely related and and energy are directly related.So, short means high and thus, high E.Since talking about emission, transitionfrom a high state to a lower state.The energy gap between n=6 and n=1 is greater than the energy gap between n=6 and n=3

For the elements Be, B, N, O, the first ionization energy increases in the order: A. Be < O < B < N B. Be < B < N < O C. B < Be < O < N D. B < Be < N < O E. Be < B < O < N

B. Be < B < N < O

16. Identify the main-group element X that could form the compound Cl- X- Cl A. C B. O C. N D. F E. P

B. O

Which of the following has the largest radius? A. Ca2+ B. S2- C. S D. K+ E. Cl-

B. S2-

Write the condensed electron configuration for the ion Ti2+. A. [Ar] 4s23d2 B. [Ar] 3d2 C. [Ar] 4s13d1 D. [Ar] 4s14d1 E. [Ar] 4d2

B. [Ar] 3d2

Write the electron configuration for the element iron. A. 1s22s22p63s23p63d8 B. 1s22s22p63s23p64s24d6 C. 1s22s22p63s23p64s23d6 D. 1s22s22p63s54f11 E. 1s22s22p63s24f14

C. 1s22s22p63s23p64s23d6

Which of the following molecules or ions would exhibit resonance? A. C2H2 B. Br2 C. CO32 D. CO E. SiH4

C. CO3 2

Which of the following statements regarding spectra is incorrect? A. Sunlight produces a continuous spectrum. B. A heated ionic compound produces a line spectrum. C. Several elements can produce the same line spectrum. D. If you know the wavelength of a line in a spectrum, the energy of the light associated with that line can be calculated. E. If you know the wavelength of a line in a spectrum, the frequency of the light associated with that line can be calculated.

C. Several elements can produce the same line spectrum.

f the size of a fluorine atom is compared to the size of a fluoride ion, A. They would both be the same size. B. The atom is larger than the ion. C. The ion is larger than the atom. D. The size difference depends on the reaction.

C. The ion is larger than the atom.

The correctly drawn Lewis formula for HCN will have __________. A. 2 single bonds and 5 pairs of nonbonding electrons B. 1 single bond, 1 double bond, and 3 pairs of nonbonding electrons C. 2 double bonds and 2 pairs of nonbonding electrons D. 1 single bond, 1 triple bond, and 1 pair of nonbonding electrons E. 2 double bonds and 1 pair of nonbonding electrons

D. 1 single bond, 1 triple bond, and 1 pair of nonbonding electrons

How many unpaired electrons are in the ground state of phosphorous? A. 0 B. 1 C. 2 D. 3 E. 5

D. 3

Arrange the following bonds in order of increasing polarity: Cl-S, Cl-P, Cl-Si, Cl-Cl A. Cl-S < Cl-P < Cl-Si < Cl-Cl B. Cl-S < Cl-Si < Cl-P < Cl-Cl C. Cl-Si < Cl-S < Cl-Cl < Cl-P D. Cl-Cl < Cl-S < Cl-P < Cl-Si E. Cl-Cl < Cl-P < Cl-Si < Cl-S

D. Cl-Cl < Cl-S < Cl-P < Cl-Si

Which of the molecules in the above figure is/are most likely to have unshared electron pairs on the central atom? A. I, II, and III B. I and II C. I, III, and IV D. II only E. not enough information

D. II only

Which of the following elements has the smallest atomic radius? A. Bi B. P C. As D. N

D. N

Of the four lines in the hydrogen line spectrum, which transition results in the emission of light with the lowest frequency? A. n = 6 n = 2 B. n = 5 n = 2 C. n = 4 n = 2 D. n = 3 n = 2

D. n = 3 n = 2 Lowest frequency means lowest energy Lowest energy means that the difference between the two states are the smallest

List the following colors of visible light from lowest energy to highest energy: green, blue, yellow, red, violet. A. red < yellow < green < blue < violet B. violet < yellow < green < blue < red C. blue < violet < green < red < yellow D. violet < blue < green < yellow < red E. yellow < red < green < violet < blue

D. violet < blue < green < yellow < red

What is the photon energy of light that has a wavelength of 465 nm?

E = hc/wavelength Wavelength= 465 nm = 4.65 x 10‐7m h = 6.626 x 10‐34J s c = 3 x 108m/s E = (6.626 x 10‐34J s)(3 x 108m/s)/(4.65 x 10‐7m) E = 4.27 x 10‐19J Answer: C: 4.27 x 10^-19J

What is the energy associated with one photon that has a frequency of 5.09 x 10^14s-1?

E = hv h = 6.626 x 10-34J-s v = 5.09 x 1014s-1 E = (6.626 x 10-34J-s)(5.09 x 1014s-1) E = 3.37 x 10^-19J

The condensed electron configuration [Kr] applies to all of the following species except: A. Br- B. As3- C. Se2- D. Sr2+ E. Cs-

E. Cs-

Predict the molecular shape and give the approximate bond angles of the OF2 molecule. A. bent, 109.5o B. trigonal planar, 120o C. tetrahedral, 109.5o D. trigonal pyramidal, < 109.5o E. bent, < 109.5o

E. bent, < 109.5o

A laser produces radiation with a frequency of 4.69 x 1014s-1. What is the wavelength of this radiation? A. 1.41 x 10^23m B. 639 nm C. 1.56 x 10^6m D. 6.39 x 10^-16nm

c = wavelength x frequency c = 3 x 108m/s Wavelength = 4.69 x 10^14s-1 Wavelength = [(3 x 108m/s )/(4.69 x 1014s-1)] = 6.39 x 10-7m =639 nm = Answer: B. 639 nm

Yellow light has a wavelength of 589 nm. What is the frequency of this radiation?

c = wavelength x frequency c = 3 x 108m/s wavelength = [589 nm x ( 1 x 10-9m1 nmc/=(3 x 108m/s )]/(5.89 x 10-7m) =5.09 x 10^14 s-1