How do you write an isotope hyphen notation?

In isotopic notation, the mass number of the isotope is written as a superscript in front of the chemical symbol for that element. In hyphen notation, the mass number is written after the name of the element.

For example, in isotopic notation, the isotope of carbon that has a mass number of twelve would be represented as #"^12C#. In hyphen notation, it would be written as carbon-12.

Key Questions

  • Isotopes are atoms of the same element that differ in the number of neutrons in their atomic nuclei. All atoms of the same element have the same number of protons, which is the atomic number of that element. However, because different isotopes have different numbers of neutrons, they can differ in mass number, which is the sum of the protons and neutrons in the nucleus.

    Isotope notation, also known as nuclear notation, is important because it allows us to use a visual symbol to easily determine an isotope's mass number, atomic number, and to determine the number of neutrons and protons in the nucleus without having to use a lot of words.

    How do you write an isotope hyphen notation?

    Additionally, #"N"="A"-"Z"#

    Example 1: What is the isotopic notation for the isotope carbon-14?

    From the periodic table, we see that the atomic number (number of protons) for the element carbon is #6#. The name carbon-14 tells us that this isotope's mass number is #14#. The chemical symbol for carbon is #"C"#. Now write the isotopic notation for carbon-14.

    #""_6^14"C"#

    We can determine the number of neutrons as #14-6=8# neutrons.

    Example 2. Given the isotopic notation #""_22^48"Ti"#, identify the following:

    a) Name of the isotope
    b) Mass number
    c) Atomic number
    d) Number of protons
    e) Number of neutrons.

    Answers:

    a) titanium-48
    b) #48#
    c) #22#
    d) #22#
    e) #48-22=26#

  • Isotopes are basically atoms which have the same no. of protons but different no. of neutrons at its nucleus.

    OR...

    Isotopes are atoms that have the same proton no. but different nucleon no.

    The chemical properties of an element is determined by its electronic configuration, which is then determined by the no. of protons it has. Since isotopes have the same no of protons at its nucleus, they have the same chemical properties.

    However the fact that they have different no. of neutrons means that the isotopes will have different physical properties (e.g. density, mass). For example, if there are two isotopes with different nucleon no., the one which has a higher nucleon no. will be more dense than the other one, since it has more no. of neutrons at its nucleus.

What is the hyphen notation for the isotope with 15 electrons and 15 neutrons?

The mass number will be 30 because the mass number is the sum of the atomic number and the number of neutrons. Therefore, the isotope in hyphen notation is Phosphorus-30.

How can you represent the isotopes using hyphen notation and nuclear symbol?

Nuclear Notation Note: in hyphen notation, the number after the hyphen is the mass number (protons + neutrons). For the Periodic Table, the Atomic Number is on top and the average atomic mass is on the bottom. For nuclear notation, the mass number of the isotope goes on top and the atomic number goes on the bottom.