NWA Chem Term 2

Rutherford made important contributions to atomic theory. What did his model fail to explain?

• location of protons

• why the negatively charged electrons were not pulled into the positively charged nucleus

• location of neutrons

• none of the above

What is the structural difference between Nitrogen-14 and Nitrogen-15?

• Nitrogen-14 and Nitrogen-15 have the same number of neutrons

• Nitrogen-14 has 7 protons and 7 neutrons; Nitrogen-15 has 7 protons and 8 neutrons

• Nitrogen-14 has 8 protons and 7 neutrons; Nitrogen-15 has 7 protons and 7 neutrons

• Nitrogen-14 has 7 protons and 8 neutrons; Nitrogen-15 has 7 protons and 8 neutrons

Two or more forms of the same element will have the same number of protons, but different numbers of neutrons. This is referred to as a(n) ______.

• isotope

• mass number

• atomic number

• electron number

Which of the following statements is true about the element that is represented in the picture?

• The element is an isotope of aluminum, and it has 13 neutrons and 14 protons.

• The element is an isotope of aluminum, and it has 13 protons and 14 neutrons.

• The element is an isotope of cobalt, and it has 13 protons and 14 neutrons.

• The element is an isotope of cobalt, and it has 14 protons and 13 neutrons.

How do you find the mass of a calcium atom?

• add the number of protons and neutrons

• add the number of protons and electrons

• add the number of neutrons and electrons

• add the number of protons, neutrons, and electrons

Which statement describes how electrons fall from the excited state of energy back to the ground state?

• Energy is absorbed

• Energy is released and a photon of light is emitted

• the electron seeks energy

• none of the above

Which of the flowing statements is true regarding subatomic particles?

• protons and electrons are located inside the nucleus

• protons and neutrons are located inside the nucleus

• protons and electrons are located outside of the nucleus

• neutrons are located outside of the nucleus

What is the atomic number?

• the number of protons
• the number of protons and neutrons
• the number of neutrons
• the number of protons and electrons

What is the mass number defined as?

• the number of protons
• the number of protons and neutrons
• the number of neutrons
• the number of protons and electrons

What is the mass number of this atom?

• 1

• 3

• 4

• 7