Each isotope of Oxygen has a different number of neutrons
<h3>Further explanation
</h3>
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
The answer is <span>a total of eight valence electrons
hope this help
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<span>conductor because it conducts the electrons</span><span />
Answer: Bacterial species where observed Typical number on cell Distribution on cell surface
Escherichia coli (common pili or Type 1 fimbriae) 100-200 uniform
Neisseria gonorrhoeae 100-200 uniform
Streptococcus pyogenes (fimbriae plus the M-protein) ? uniform
Pseudomonas aeruginosa 10-20 polar
Explanation:
Pili are structures that extend from the surface of some bacterial cells.
These are hollow, non-helical, filamentous appendages.
Hope it helps you