Question

29 essay 1 point
what is meant by an atom being in its excited state?

30 multiple choice 1 point
which of the following colors of light has the shortest wavelength?
blue
red
green
yellow

31 multiple choice 1 point
according to periodic trends, which metal has the highest ionization energy?
cs
rb
li

32 multiple choice 1 point
elements in group 17 are considered _______
halogens
noble gases
alkali metals

33 multiple choice 1 point
chlorine gas is considered a ______?
halogen

Explanation:

Define excited state of an atom

Using the Excited State knowledge point, an atom is in an excited state when one or more of its electrons have absorbed energy and transitioned to a higher energy level than their lowest possible energy state (the ground state). This state is temporary and unstable.

Analyze visible light wavelengths

Using the Electromagnetic Spectrum Wavelengths knowledge point, visible light wavelengths range from approximately \(400\text{ nm}\) (violet/blue) to \(700\text{ nm}\) (red). Among the options provided (Blue, Red, Green, Yellow), blue light has the highest frequency and therefore the shortest wavelength.

Determine ionization energy trend

Using the Periodic Trends and Ionization Energy knowledge points, ionization energy increases up a group. For the alkali metals listed (Cs, Rb, Li), lithium (\(\text{Li}\)) is at the top of the group, meaning it has the smallest atomic radius and the highest ionization energy.

Identify Group 17 elements

Group 17 elements on the periodic table are known as the halogens. These elements are highly reactive nonmetals with seven valence electrons.

Classify chlorine gas

Chlorine (\(\text{Cl}\)) is located in Group 17 of the periodic table, which means chlorine gas (\(\text{Cl}_2\)) is classified as a halogen.

Answer:

Question 29

An atom is in an "excited state" when one or more of its electrons have absorbed energy and jumped to a higher energy level, leaving its lowest energy configuration (the ground state).

Question 30

• (A) Blue (Correct answer)
• (B) Red
• (C) Green
• (D) Yellow

Question 31

• (A) Cs
• (B) Rb
• (C) Li (Correct answer)

Question 32

• (A) halogens (Correct answer)
• (B) noble gases
• (C) alkali metals

Question 33

• (A) halogen (Correct answer)