if oxygen is presented in diatomic molecula 02 then why it is only one atom in h2o (water)
Answers
Answer:
Oxygen is diatomic in its elemental form — that is, when it is not bonded to other elements.
A lone oxygen atom has six valence electrons. It would be more stable if it had eight valence electrons, so it tries to fill in its two vacancies by either stealing electrons from other atoms, or by sharing electrons with other atoms.
When there are no other atoms but oxygen present, oxygen atoms will share electrons with each other to complete each others’ “octets” (set of eight valence electrons)
When oxygen is with other elements (and when it is energetically feasible to do so), it preferentially bonds with them. When oxygen is bonded with other elements, it doesn’t have to be doubled up to fulfill its 8 valence electron requirement.
For example, in a water molecule, one oxygen atom shares electrons with two hydrogen atoms. Because each hydrogen atom shares one electron, that completes oxygen’s octet.
So it’s really just a question of what’s available. When nothing is available but other oxygen atoms, oxygen forms diatomic molecules with the formula O 2 .
When hydrogen is available (and when you provide a spark to get the reaction going) oxygen forms molecules with the formula H 2 O.
Explanation:
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