Answer:
I think the answer is 4) 41
Explanation:
APE= atomic number, proton and the electrons are the same number
MAN= mass = atomic number - neutrons
121 - 80 = 41
i haven't done this in a while so hope this helps :)
Answer:
3.59 moles
Explanation:
Hopefully this helps! :)
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I looked up what is the molecular formula for Phosphine and got this: PH3
Hope this helps! Let my know if this was correct.
The valence electron does the halogens possess are 7
- Valence electrons are found in the outermost energy level of an atom
- They are involved in the formation of chemical bonding with other atoms.
- The halogens elements are found in group 17 on the periodic table
- The halogens include fluorine, chlorine, bromine, iodine and astatine.
- They have seven valence electrons, so they are extremely reactive as they only need one more to fill their outer shell.
- By octet rule we can say that the electron with 8 outer most shell is full and stable.
Hence the halogens posses 7 valence electron
Learn more about the valence electron on
brainly.com/question/13552988
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