Why does hydrogen (H) have a different subscript in each chemical formula of various substances?

• A. Because hydrogen always pairs with itself before bonding with other elements.
• B. Because hydrogen can only exist as H2 in all compounds.
• C. Because the subscript for hydrogen is determined by its atomic number.
• D. Because hydrogen forms different numbers of bonds depending on the compound it is in.

Answer: (D)

Verified step by step guidance

1. Understand that the subscript in a chemical formula indicates the number of atoms of an element present in a molecule or compound.
2. Recognize that hydrogen can form different numbers of bonds (usually one bond) depending on the compound it is part of, which affects how many hydrogen atoms are bonded to other atoms.
3. Know that hydrogen does not always pair with itself (H2) in compounds; it can be bonded to other elements in varying amounts, leading to different subscripts.
4. Realize that the atomic number of hydrogen (which is 1) does not determine the subscript in a chemical formula; the subscript depends on the compound's structure and bonding.
5. Conclude that the subscript for hydrogen varies because hydrogen forms different numbers of bonds in different compounds, resulting in different numbers of hydrogen atoms in the chemical formulas.