Each isotope of Oxygen has a different number of neutrons
<h3>Further explanation
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The elements in nature have several types of isotopes
Atomic mass is the average atomic mass of all its isotopes
Isotopes are atoms has the same number of protons but has a different number of neutrons.
So Isotopes are elements that have the same Atomic Number (Proton)
Some of the isotopes of oxygen are:

Each isotope has 8 protons and 8 electrons but has a different number of neutrons
For O-16: number of neutrons = 16-8 = 8
For O-17: number of neutrons = 17-8 = 9
For O-18: number of neutrons = 18-8 = 10
Answer:
He developed the concept of concentric electron energy levels
Explanation:
Before Bohr's model, Rutherford's model was proposed. This model explains most of the properties of the atom but failed to explain the stability of the atom.
As per Rutherford's model, electrons revolve around the nucleus in the orbit.
But revolving electron in their orbit around nucleus would give up energy and so gradually move towards the nucleus and therefore, eventually collapse.
Bohr's proposed that the electrons around the nucleus move orbit of fixed energy called "stationary states". Electrons in these stationary states do not radiate energy.
Therefore, proposal of concentric electron energy levels refine the atomic models.
Answer:
Geosphere and hydrosphere is the correct answer to the given question .
Explanation:
The Volcanic eruption substances alter ecosystems and create pollutants and gasses in the environment as well as in the waters.The Volcanic eruption is effected the climate as well as the weather of the environment system .The volcanic eruption is simply effected the rainfall of the climate environment.
- The Geosphere and hydrosphere communicate when the amount of rain rises in the region of the following a volcanic eruption.
- All the other option are incorrect because these layer is not involved in the rising in the region of the volcanic eruption.