The atomic and mass numbers for four different atoms are given below. which two are isotopes? atom atomic# mass# w 50 117 x 50 119 y 51 119 z 52 117

Atom W and atom X are isotopes.

Explanation:

Isotopes are defined as the substances which have same atomic number but different mass number.

We are given:

For atom W:

Atomic number = 50

Mass number = 117

For atom X:

Atomic number = 50

Mass number = 119

For atom Y:

Atomic number = 51

Mass number = 119

For atom Z:

Atomic number = 52

Mass number = 117

As, atom W and atom X have same atomic number. Thus, they are isotopes.