Answer:
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Explanation:
Isotopes are atoms of the same element that have different numbers of neutrons but the same number of protons and electrons . The difference in the number of neutrons between the various isotopes of an element means that the various isotopes have different masses.
example:chlorine is an example of an isotope it has a proton number of 17 and a mass number of 35 in some cases they have a proton number of 17 and a mass number of 37 there is difference in the number of neutron to calculate this we do it this way.for the first one
mass number=proton+neutron
neutron=mass number-proton
neutron=35-17
neutron=18
for the second one
neutron=37-17
neutron=20
