CHEM Exam 3 REview

How many possible wavelengths can be emitted if an electron moves from n = 4 to n = 2, what about from n = 3 to n = 0

• 3

• 4

• 3 and 6

• 4 and 5

Arrange the following groups of atoms in order of increasing size

1. Rb, Na, Be

• Rb, Na, Be

• Be, Rb, Na,

• Be, Na Rb

• Na, Be, Rb

Using the periodic table, write the expected ground state electron configurations for the following:

1. The fourth element in Group 2

• 1s2 2s2 2p6 3s2 3p6 4s2 4p6 5s2

• 1s2 2s2 2p6 3s2 3p6 4s2 4p6

• 1s2 2s2 2p6 3s2 3p6 4s2 4p4

• 1s2 2s2 2p6 3s2 3p6 4s2 4p6 5s1

Using the periodic table, write the expected ground state electron configurations for the following:

1. An element with three unpaired 3p electrons

• 1s2 2s2 2p6 3s2 3p5

• 1s2 2s2 2p6 3s2 3p4

• 1s2 2s1 2p6 3s2 3p3

• 1s2 2s2 2p6 3s2 3p3

Octyl methoxycinnamate and oxybenzone are common ingredients in sunscreen applications. These compounds work by absorbing ultraviolet (UV) B light (wavelength 280-320 nm), the UV light most associated with sunburn symptoms. What frequency range of light do these compounds absorb?

• 2.07*10^15-9.58*10^14 nm

• 1.58*10^14-7.63*10^15 nm

• 1.28*10^14-8.46*10^14 nm

• 1.07*10^15-9.38*10^14 nm

Calculate the Change in energy if a gas absorbs 45 kJ of heat and does 29 kJ of work on the surroundings

• 16 kJ
• 0 kJ
• 74 kJ
• -16 kJ

It takes 7.21 x 10-19 J of energy to remove an electron from an iron atom. What is the maximum wavelength of light that can do this?

• 327 nm

• 276 nm

• 238 nm

• 308 nm

If the internal energy of a thermodynamic system is increased by 300. J while 75 J of expansion work is done, how much heat was transferred and in which direction, to or from the system?

• -375 J
• 75 J
• 300 J
• 375 J