Question

What are isotopes?

Answer 1

"each of two or more forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei, and hence differ in relative atomic mass but not in chemical properties; in particular, a radioactive form of an element."

Answer 2

For example Chlorine of atomic mass 35.5 and 37. They are so because of different number of neutrons which have mass but no +ve or -ve value. And since its the atomic number which determines the chemical properties, there is no change in chemical properties between isotopes of an element.

Answer 3

Okay, so out of these choices which represents a pair of isotopes?
14C and 14N

Br and Br2

9B and 11B

16O and 16O2-

Answer 4

9B and 11B


If the 9 and 11 are the atomic weight you are referring to. !4C and 14N are two different elements all together. Br and Br2 are the atomic and molecular form of the element. 16O and 16o2-, is the change in electrons of the element. Since it's the change in weight which forms the isotope, it's 9B and 11B