The correct answer is A. Alkali metals.
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Answer:
It is reactive because it has to gain an electron to have a full outermost energy level.
Explanation:
The electron configuration of oxygen is 1s2,2s2 2p4.
Oxygen is in group six in the periodic table so it has six electrons in its valence shell. This means that it needs to gain two electrons to obey the octet rule and have a full outer shell of electrons (eight).
The chemical formula C₂H₆O, which is designated as option D, is equivalent to this structural formula.
<h3><u>What is a Chemical Formula ?</u></h3>
Chemical element symbols, numbers, and occasionally additional symbols like parentheses, dashes, brackets, commas, and plus (+) and minus () signs are used in a chemical formula to represent information about the chemical proportions of the atoms that make up a certain chemical compound or molecule.
- An empirical formula represents by symbols, such as Na for sodium and Cl for chlorine, with subscripts that show the relative number of atoms in each.
- The composition of any member of an entire class of compounds can be represented by a general formula, a sort of empirical formula.
To know more about Chemical formulas, refer to:
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