Question

Question 3

1. The electronic structure of atoms and molecules may be investigated using photoelectron spectroscopy. An electron in a photoelectron spectrometer is accelerated from rest by a uniform electric field to a speed of 420 km s⁻¹ in 10 µs. Determine the kinetic energy of the electron?

a.

8.0 x 10-2 N.m

b.

1.6 x 10-25 N.m

c.

3.8 x 10-25 N.m

d.

4..0 x 10-2 N.m

Question 4

1. The electronic structure of atoms and molecules may be investigated using photoelectron spectroscopy. An electron in a photoelectron spectrometer is accelerated from rest by a uniform electric field to a speed of 420 km s⁻¹ in 10 µs. Determine the magnitude of the work done on the electron.

a.

1.6 x 10-25 J

b.

8.0 x 10-2 J

c.

1.6 x 10-19 J

d.

4.0 x 10-2 J

10 points

Question 5

1. The most probable distance of an electron from the nucleus in the lowest energy state of a hydrogen atom is called the Bohr radius: a₀ = 52.9 pm. What is the electrostatic potential energy of interaction between the nucleus and the electron at this separation?

a.

(-) 5.48 x 10 -18 J

b.

(-) 5.48 x 10 -17 J

c.

(-) 4.36 x 10 -18 J

d.

(-) 8.72 x 10 -18 J

10 points

Question 6

1. At sea level, where the pressure was 104 kPa and the temperature 21.1 °C, a certain mass of air occupied 2.0 m³. To what volume will the region expand when it has risen to an altitude where the pressure and temperature are 880 Pa and −52.0 °C, respectively?

a.

0.18 m3

b.

17.8 m3

c.

-9.9 m3

d.

178 m3

Question 7

1. A gas mixture is used to simulate the atmosphere of another planet consists of 320 mg of methane, 175 mg of argon, and 225 mg of nitrogen. The partial pressure of nitrogen at 300 K is 15.2 kPa. Calculate the volume of the mixture.

a.

1.32 x 10-3 m3

b.

0.28 m3

c.

1.32 m3

d.

36.92 m3

10 points

Question 8

1. Using the same given provided in question #7, calculate the total pressure of the mixture.

a.

6.1 kPa

b.

378.9 kPa

c.

61.3 kPa

d.

61.3 Pa

10 points

Question 9

1. The composition of planetary atmospheres is determined in part by the speeds of the molecules of the constituent gases because the faster-moving molecules can reach escape velocity and leave the planet. Calculate the mean speed of CH₄ molecules at 77K and 1500K.

a.

346 m/s, 1308 m/s

b.

346 m/s, 1527 m/s

c.

681 m/s, 1247 m/s

d.

681 m/s, 1527 m/s

Question 10

1. Please calculate the pressure exerted by 1.0 mol C₂H₆ behaving as a van der Waals gas when it is confined under the following condition at 1000 K in 100 cm³.

a.

3346 atm

b.

1718 atm

c.

2267 atm

d.

4756 atm

Answer 1