There are two main isotopes of chlorine. 75% of chlorine atoms have a mass number of 35, while 25% have a mass number of 37. use this information to work out the relative atomic mass of chlorine

General
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there are two main isotopes of chlorine. 75% of chlorine atoms have a mass number of 35, while 25% have a mass number of 37. use this information to work out the relative atomic mass of chlorine.

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LectureNotes said there are two main isotopes of chlorine. 75% of chlorine atoms have a mass number of 35, while 25% have a mass number of 37. Use this information to work out the relative atomic mass of chlorine.

Answer:
To calculate the relative atomic mass of chlorine, we use the given isotopic abundances and their respective mass numbers. The relative atomic mass is the weighted average of the atomic masses of the isotopes based on their natural abundance.

Here are the steps to calculate it:

  1. Identify the mass numbers and their abundances:

    • Isotope with mass number 35: ( 75% ) or ( 0.75 )
    • Isotope with mass number 37: ( 25% ) or ( 0.25 )

  2. Calculate the contribution of each isotope to the relative atomic mass:

    • Contribution of isotope with mass number 35:
      35 \times 0.75 = 26.25
    • Contribution of isotope with mass number 37:
      37 \times 0.25 = 9.25

  3. Sum the contributions to find the relative atomic mass:

    \text{Relative atomic mass} = 26.25 + 9.25 = 35.5

Therefore, the relative atomic mass of chlorine is \boxed{35.5}.