The most common form of calcium has 20 protons, 20 nuetrons and 20 electrons. Which of the following element is an isotope of calcium?

a. an atom with 21 protons, 20 neutrons, 21 electrons
b. an atom with 20 protons, 20 neutrons, 18 electrons
c. an atom with 21 protons, 21 neutrons, 21 electrons
d. an atom with 20 protons, 21 neutrons, and 20 electrons


Ans: d. an atom with 20 protons, 21 neutrons, and 20 electrons

Biology & Microbiology

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