each isotope of a given element has a different mass number. For example, carbon-12, carbon-13<span> and carbon-</span>14<span> are </span>three<span> isotopes of the element carbon with mass numbers </span>12<span>, </span>13<span> and </span>14<span> </span>
Answer:
The last option
Explanation:
The Bohr model was an attempt to explain atomic hydrogen's spectrum. This was done by establishing energy levels of separate electron orbits in the atom.Thos model was followed by the Schrödinger model.
