Regents Chemistry Test Preparation Practice Excited States Bright Line Spectrum

Which element is paired with an excited-state electron configuration for an atom of the element?*

(1) Ca: 2-8-8-2

(2) Na: 2-8-2

(3) K: 2-6-8-3

(4) F: 2-8

Which electron configuration represents a selenium atom in an excited state?*

(1) 2-7-18-6

(2) 2-7-18-7

(3) 2-8-18-6

(4) 2-8-18-7

An electron in a sodium atom gains enough energy to move from the second shell to the third shell. The sodium atom becomes*

(1) a positive ion

(2) a negative ion

(3) an atom in an excited state

(4) an atom in the ground state

Which electron configuration represents an atom of chlorine in an excited state?*

(1) 2-7-7

(2) 2-7-8

(3) 2-8-7

(4) 2-8-8

Which electron configuration represents the distribution of electrons in a potassium atom in the ground state?*

(1) 2-8-8-1

(2) 2-8-7-2

(3) 2-8-5

(4) 2-7-6

Which electron configuration represents the electrons of an atom in an excited state?*

(1) 2–2

(2) 2–2–1

(3) 2–8

(4) 2–8–1

Which electron configuration represents the electrons in an atom of sodium in the ground state at STP?*

(1) 2-8-1

(2) 2-7-2

(3) 2-8-6

(4) 2-7-7

A bromine atom in an excited state could have an electron configuration of*

(1) 2-8-18-6

(2) 2-8-18-7

(3) 2-8-17-7

(4) 2-8-17-8

Which electron configuration represents the electrons of a sulfur atom in an excited state?*

(1) 2-6-6

(2) 2-7-7

(3) 2-8-4

(4) 2-8-6

Which electron configuration represents the electrons in an atom of Ga in an excited state?*

(1) 2-8-17-3

(2) 2-8-17-4

(3) 2-8-18-3

(4) 2-8-18-4

Which electron configuration represents the electrons of an atom of neon in an excited state?*

(1) 2-7

(2) 2-8

(3) 2-7-1

(4) 2-8-1

Which electron configuration represents a potassium atom in an excited state?*

(1) 2-7-6

(2) 2-8-5

(3) 2-8-8-1

(4) 2-8-7-2

Which electron configuration represents an atom of chlorine in an excited state?*

(1) 2-8-7-2

(2) 2-8-7

(3) 2-8-8

(4) 2-7-8

Base your answers to questions 14 on the information below and on your knowledge of chemistry.

The Bohr model of the atom was developed in the early part of the twentieth century. A diagram of the Bohr model for one atom, in the ground state, of a specific element is shown below. The nucleus of this atom contains 4 protons and 5 neutrons.

periodic-table, identification-of-element fig: chem62015-exam_g13.png

Using the Bohr model, describe the changes in electron energy and electron location when an atom changes from the ground state to an excited state.*

Base your answers to questions 15 on the information below and on your knowledge of chemistry.

Fireworks that contain metallic salts such as sodium, strontium, and barium can generate bright colors. A technician investigates what colors are produced by the metallic salts by performing flame tests. During a flame test, a metallic salt is heated in the flame of a gas burner. Each metallic salt emits a characteristic colored light in the flame.

Explain why the electron configuration of 2-7-1-1 represents a sodium atom in an excited state.*