4. Chlorine-35 atom and Chlorine-37 atom are called isotopes...Use these two examples to explain what is 'isotopes'

isotopes are differents atom of the same elements with the same amount of protons but differents amount of neutrons. Clorine-35 has 17 protons and 18 neutrons. Clorine-37 has 17 protons and 20 neutrons. in conclusion, they have the same number of protons (17) but different number of neutrons (clorine 35-18, clorine 37- 20)  this show that they are isotopes.

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