Isotopes and Atomic Mass Concepts

Miss Kerney explains atomic theory focusing on isotopes and atomic mass. The video covers how isotopes differ in neutron number, affecting mass number, and how to calculate atomic mass using isotopic abundance. Example problems with chlorine, neon, and silver isotopes illustrate these concepts.

What happens when the number of neutrons in an atom is changed?

• The atom's atomic number changes.

• The atom becomes a different element.

• The atom becomes an isotope.

• The atom loses its charge.

How do isotopes of an element differ from each other?

• In their chemical behavior.

• In the number of neutrons.

• In the number of electrons.

• In the number of protons.

What is the atomic number of an element?

• The average mass of the element's isotopes.

• The number of neutrons in the nucleus.

• The total number of protons and neutrons.

• The number of protons in the nucleus.

How is the atomic mass of an element determined?

• By adding the number of protons and neutrons.

• By measuring the element's density.

• By averaging the masses of its isotopes.

• By counting the number of protons.

What is fractional abundance?

• The fraction of an isotope's mass to the total mass.

• The fraction of an isotope's abundance to 100.

• The ratio of isotopes in a compound.

• The percentage of an isotope in a sample.

In the chlorine isotopes problem, what is the first step to find the average atomic mass?

• Add the masses of the isotopes.

• Subtract the smaller mass from the larger mass.

• Divide the mass of each isotope by its atomic number.

• Multiply the mass of each isotope by its fractional abundance.

What is the average atomic mass of chlorine as calculated in the video?

• 35.49

• 36.00

• 37.00

• 34.00

In the silver isotopes problem, what equation is used to find the percent abundance?

• x + y = 1

• x - y = 0

• x / y = 1

• x * y = 1

What is the accepted atomic mass of silver given in the video?

• 108.00 AMU

• 107.87 AMU

• 106.00 AMU

• 109.00 AMU

What is the percent abundance of silver-107 as calculated in the video?

• 50.0%

• 56.5%

• 43.5%

• 60.0%