Question

Two atoms have the same number of protons but different numbers of neutrons. What can you conclude about these two atoms? A-they are the same element B-they are the same isotope C-they have the same mass D-thay have the same charge.

Answer 1

Since the two atoms have the same number of protons they are the same element. The fact that they have different numbers of neutrons makes them isotopes. The best answer is A.

Answer 2

Answer: A-they are the same element

Explanation: An element is characterized by its atomic number or the number of protons.

Two atoms having the same number of protons but different numbers of neutrons will have same atomic number but different mass number.Thus they are isotopes of the same element.

As Atomic number = Number of protons

Mass number = number of protons + number of neutrons

For example: $_1^1H$ and $_1^2H$  are both isotopes of Hydrogen with same number of protons but different number of neutrons.