Isotopes Uncovered: The Relationship Between Atomic Number and Mass Number

The video explains isotopes using carbon-12 and carbon-13 as examples. It covers the properties of isotopes, including their identical chemical properties and differing nuclear properties due to varying neutron numbers. The video also demonstrates how to identify isotopes using atomic and mass numbers, and provides practice problems and a true or false quiz to reinforce learning.

What is the atomic number of carbon, and why is it significant?

• 12, because it shows the number of protons.

• 6, because it indicates the number of neutrons.

• 12, because it represents the mass number.

• 6, because it identifies the element as carbon.

Why do isotopes have different mass numbers?

• Because they have different chemical properties.

• Because they have different atomic numbers.

• Because they have different numbers of neutrons.

• Because they have different numbers of protons.

Which of the following is true about isotopes?

• They have different chemical properties.

• They have the same number of protons.

• They have the same mass numbers.

• They have different atomic numbers.

What must be true for two substances to be isotopes of each other?

• They must have the same number of neutrons.

• They must have different chemical properties.

• They must have the same atomic number.

• They must have the same mass number.

If a substance has an atomic number of 15 and a mass number of 32, what is the number of neutrons?

• 17

• 32

• 47

• 15

How do you determine the element of an isotope given its atomic number?

• By comparing it to known isotopes.

• By looking at the mass number.

• By counting the number of neutrons.

• By checking the periodic table for the atomic number.

What is the atomic symbol for an isotope with 7 protons and 8 neutrons?

• N-15

• O-15

• C-15

• N-14

Which statement is true about the chemical properties of isotopes?

• They change with the number of neutrons.

• They vary because isotopes have different mass numbers.

• They are identical because isotopes are the same element.

• They differ due to different atomic numbers.

What is the significance of the mass number in isotopes?

• It determines the chemical properties.

• It is the sum of protons and neutrons.

• It indicates the number of electrons.

• It is always equal to the atomic number.

Which of the following is a false statement about isotopes?

• Isotopes have different mass numbers.

• Isotopes have different nuclear properties.

• Isotopes have the same number of neutrons.

• Isotopes have the same atomic number.