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Define valency? What is the valency of the element with atomic number 8. What is the compound by the element with hydrogen.
 
Valency is defined as the combining .
 
Atomic number \(8\) element is . Its valency is .
 
The hydrogen (H) and oxygen (O) atoms that combine to form molecules are bound together by covalent bonds.
 
\(H_2\) + \(O_2\) \(\rightarrow\) .