MCAT Question of the Day
    •

    Q:

    		 The atomic number of an element refers to:
    		 

    A

    		 the number of electrons of an atom.

    B

    		 the number of protons of an atom.

    C

    		 the number of neutrons of an atom.

    D

    		 the sum of protons and neutrons of an atom.



    Periodic Table |
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