What is the maximum number of covalent bonds that an oxygen atom with atomic number 8 can make with hydrogen?

The maximum number of covalent bonds that an oxygen atom with atomic number 8 can make with hydrogen is: 2.

Valency can be defined as a measure of the combining power of a chemical element with other atoms to form a molecule or chemical compound.  Typically, valency is measured by the amount of hydrogen atoms that a chemical element can combine with or displace to form a molecule or chemical compound.

Valence electrons can be defined as the number of electrons present in the outermost shell of an atom. Valence electrons are used to determine whether an atom or group of elements found in a periodic table can bond with others.

From the periodic table, we know that an oxygen atom has an atomic number of eight (8). Thus, oxygen has six (6) electrons in its valence shell and two (2) empty shells to form a covalent bond with hydrogen.  

Generally, the maximum number of electrons an atom can hold in its valence shell is eight (8) and since oxygen has has six (6) electrons in its valence shell; it ultimately implies that the maximum number of covalent bonds that an oxygen atom with atomic number of eight (8) can make with hydrogen is two (2) covalent bonds.

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2

Explanation:

Oxygen has 6 electrons in its valence shell.  Since an atom can have a maximum of 8 electrons in the valence shell, oxygen has 2 empty spots in its valence.  This means that oxygen can make 2 single covalent bonds.

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