1.2.2 Isotopes

• Isotopes have the same atomic number but different mass numbers.


  True
• The number of neutrons in an isotope affects its mass number.


  True
• An atom is composed of protons, neutrons, and electrons.

  True
• Electrons have a negative charge and orbit the nucleus.


  True
• A helium atom has 2 protons, 2 neutrons, and 2 electrons.
• What does the mass number of an atom represent?

  Total protons and neutrons
• Isotopes are atoms of the same element that have the same number of protons
• Neutrons are located in the nucleus
• What is the composition of a hydrogen atom?

  1 proton, 0 neutrons, 1 electron
• What are two isotopes of carbon?

  Carbon-12 and Carbon-14
• The atomic number defines the identity of an element.


  True
• Isotopes of the same element exhibit similar chemical properties.

  True
• Carbon-14 is used in industry as a tracer in chemical reactions.

  False
• Isotopes of the same element have the same number of protons
• The number of protons defines the element in an atom.
• The mass number of an isotope varies due to the number of neutrons.
• A neutron has a charge of zero and is located in the nucleus.
• How many protons, neutrons, and electrons does a hydrogen atom have?

  1, 0, 1
• Carbon-12 and carbon-14 are isotopes of carbon.

  True
• The atomic number determines the element, while the mass number determines the isotope.


  True
• Why does the mass number of isotopes vary?

  Different neutron count
• Match the subatomic particle with its charge:

  Proton ↔️ Positive (+1)

  Neutron ↔️ Neutral (0)

  Electron ↔️ Negative (-1)
• The atomic number of isotopes varies due to the different number of neutrons.

  False
• The mass number of an atom is the sum of its protons and neutrons
• Carbon-12 has 6 protons and 6 neutrons
• Iodine-131 is used in medicine to treat thyroid disorders.
• What are isotopes?

  Atoms of the same element
• What does it mean for isotopes to belong to the same element?

  They are on the same row
• What remains constant for all isotopes of an element?

  Atomic number
• What is the charge and location of a proton in an atom?

  Positive, nucleus
• Arrange the subatomic particles based on their location in an atom:

  1️⃣ Protons in the nucleus

  2️⃣ Neutrons in the nucleus

  3️⃣ Electrons orbiting the nucleus
• Why do isotopes of the same element have different mass numbers?

  Different neutron count
• The atomic number of an atom is the number of protons in its nucleus.
• The number of neutrons in an isotope affects its atomic number.

  False
• Electrons orbit the nucleus in shells.


  True
• Isotopes have the same number of protons but different numbers of neutrons
• What is the mass number of carbon-14?

  14
• How is the atomic mass of an element determined in the periodic table?

  Weighted average of isotopes
• Match the isotope with its application:

  Carbon-14 ↔️ Radiocarbon dating

  Uranium-238 ↔️ Dating rocks and minerals

  Cobalt-60 ↔️ Radiation therapy for cancer