Deck 13: Inorganic Materials, Structure, Bonding in Solids, Molecular Spectroscopy, Photochemistry and Nuclear Chemistry

Question 1

Which estimates the number of electrons per cubic centimeter excited to the conduction band as a function of temperature and the band gap energy.


-Refer to Exhibit 22-2. Based solely on the equation above, which set of conditions will result in the most electrons being excited to the conduction band.

A) Low temperature, low band gap energy
B) Low temperature, high band gap energy
C) High temperature, low band gap energy
D) High temperature, high band gap energy

Answer 1

High temperature, low band gap energy

Question 2

Which estimates the number of electrons per cubic centimeter excited to the conduction band as a function of temperature and the band gap energy.

-Refer to Exhibit 22-2. The band gap of pure crystalline silicon is 1.94´10^-19 J at 300 K. How many electrons are excited from the valence band to the conduction band at this temperature in a 1.00 cm³ silicon crystal?

A) 1.70´10⁹
B) 4.80´10¹⁵
C) 0.555 N_A
D) 1.46´10⁷

Answer 2

1.70´10⁹

Question 3

Which of the following is not an acceptable location for an atom in a side-centered primitive cell?

A) (1,1,0)
B) (1, ,0)
C)
D) all of the above
E) none of the above

Answer 3

all of the above

Question 4

An element crystallizes in a body-centered cubic lattice, with a = 4.109 Å. If the element has a density of 9.95 g·cm^-3, what is the molar mass of the element?

A) 104 g·mol^-1
B) 208 g·mol^-1
C) 416 g·mol^-1
D) 831 g·mol^-1

Question 5

Which of the following will have the maximum ultraviolet absorbance at the longest wavelength?

A)
B)

C)

D)

Question 6

Which of the following symbols also represents a b particle?

A)

B)

C)

D)
E) None of the above

Question 7

pertain to a 0.25 gram sample of the ³²P nuclide which has a half life of 14.28 days and a specific activity of 1.07´10¹⁶ Bq·g^-1.


-Refer to Exhibit 19-1. What is the value of the decay constant k?

A) 7.00´10^-2 d^-1
B) 2.11´10^-2 d^-1
C) 4.85´10^-2 d^-1
D) 9.70´10^-2 d^-1

Question 8

pertain to a 0.25 gram sample of the ³²P nuclide which has a half life of 14.28 days and a specific activity of 1.07´10¹⁶ Bq·g^-1.


-Refer to Exhibit 19-1. What is the activity of the 0.25 gram sample initially?

A) 1.07´10¹⁶ Bq
B) 2.68´10¹⁵ Bq
C) 4.28´10¹⁶ Bq
D) 5.33´10¹⁵ Bq

Question 9

pertain to a 0.25 gram sample of the ³²P nuclide which has a half life of 14.28 days and a specific activity of 1.07´10¹⁶ Bq·g^-1.


-Refer to Exhibit 19-1. What is the activity of the 0.25 gram sample after 30 days?

A) 6.26´10¹⁴ Bq
B) 2.50´10¹⁵ Bq
C) 1.42´10¹⁵ Bq
D) 1.42´10¹⁴ Bq

Question 10

pertain to a 0.25 gram sample of the ³²P nuclide which has a half life of 14.28 days and a specific activity of 1.07´10¹⁶ Bq·g^-1.


-Refer to Exhibit 19-1. How long will it take for the activity of the 0.25 g sample to fall below 1 Ci? (1 Ci=3.7´10¹⁰ Bq)

A) 190 days
B) 217 days
C) 231 days
D) 259 days

Question 11

pertain to a 450 gram sample of ⁶⁰Co recovered from a decommissioned nuclear reactor. An activity of 1.11´10¹³ Bq was measured by technicians dismantling the plant.


-Refer to Exhibit 19-2. The activity of the sample was measured a year later and found to be 9.73´10¹² Bq. What is the decay constant?

A) 0.132 d^-1
B) 0.0572 d^-1
C) 3.12 d^-1
D) 0.319 d^-1