Question

Two atoms that have the same atomic number but different mass numbers are called?

Answer 1

I'm not entirely sure, but i'll try:

Theory 1 = Atomic number is the same as the proton number. The amount of number a proton has determines the element that atom is. So, for example an atom has 8 as it's atomic number and another has 8, also, as the atomic number. Meaning they are both the same element. So, the same atomic number = the same element.

Theory 2 = Ions - because the thing that determine the type of element is the proton number (which doesn't change). However, the mass number of any element can change because of ionic bonding. So, in conclusion, two atoms with the same atomic numbers but different mass numbers is called Ions.

Sorry, if this turns out to be wrong... I'm not sure which one is correct or even if any of my theories is correct, but I've got my eyes set on the 2nd theory, it makes more sense... Again, sorry, hope this helped... :)

Answer 2

Answer: isotopes

Step-by-step explanation:

The atomic number is the number of protons in the atom.

Each element is identified by the atomic number. That means that all the atomos of a giiven element have the same number of protons.

On the other hand, the atoms of a same element may differ in the number of neutrons.

The neutrons are as massive as the protons, so the mass numbers are the sum of the number of protons and number of neutrons.

So, atoms of the same element but different number of neutrons have different mass numbers are named isotopes.

Most elements in nature have isotopes. For example, there are three atoms of potassium in the nature whose mass numbers are:

1) Isotope K-39: mass number 39; it has 19 protons and 20 neutrons
2) Isotope K -40: mass number 40; it has 19 protons and 21 neutrons
3) Isotope K-41: mass number 41; it has 19 protons and 22 netrons.