How can two atoms of the same chemical element be different?

A.
They may be different allotropes of the element. Each allotrope of the same element has a different number of electrons.

B.
They may be different isotopes of the element. Each isotope of the same element has a different number of neutrons.

C.
They may be different isotopes of the element. Each isotope of the same element has a different number of electrons.

D.
They may be different allotropes of the element. Each allotrope of the same element has a different number of neutrons.

Question

How can two atoms of the same chemical element be different?	
 
 A.
They may be different allotropes of the element. Each allotrope of the same element has a different number of electrons.
 
 B.
They may be different isotopes of the element. Each isotope of the same element has a different number of neutrons.
 
 C.
They may be different isotopes of the element. Each isotope of the same element has a different number of electrons.
 
 D.
They may be different allotropes of the element. Each allotrope of the same element has a different number of neutrons.

anonymous · Answer

@ivancsc1996

anonymous · Answer

@iambatman

danjs · Answer

look up isotopes of elements, and what makes them differ from each other.

anonymous · Answer

they are different in number of neutron which is called isotopes.