Chemical Formula = C2H4O2 Total # valence electrons: 12 Draw the Lewis Structure for the 1st isomer.
The Correct Answer and Explanation is:
To draw the Lewis structure for the first isomer of the chemical formula ( C_2H_4O_2 ), which is acetic acid, we need to follow a systematic approach.
Steps to Draw the Lewis Structure:
- Count the Total Valence Electrons:
- Carbon (C) has 4 valence electrons, and there are 2 carbon atoms: ( 2 \times 4 = 8 ) electrons.
- Hydrogen (H) has 1 valence electron, and there are 4 hydrogen atoms: ( 4 \times 1 = 4 ) electrons.
- Oxygen (O) has 6 valence electrons, and there are 2 oxygen atoms: ( 2 \times 6 = 12 ) electrons.
- Total: ( 8 + 4 + 12 = 24 ) valence electrons.
- Arrange the Atoms:
- The carbon atoms are typically the central atoms. We can start by placing one carbon atom at the center and the other carbon atom attached to it. We place the oxygen atoms at the ends, with one being double-bonded to one carbon (forming a carbonyl group) and the other single-bonded (forming a hydroxyl group).
- Distribute Electrons:
- Connect the atoms with single bonds first. Each bond uses 2 electrons, and we have four single bonds initially (C-C, C=O, C-O, O-H).
- After placing the bonds, we need to check the octets. The central carbon will have four bonds, fulfilling the octet rule. The oxygen connected with a double bond will also fulfill its octet, while the hydroxyl oxygen has a single bond plus one lone pair.
- Finalize the Structure:
- The final structure can be represented as:
H O \ // C / \ H C // O | H
Explanation of the Structure:
In this structure, one carbon atom is double-bonded to an oxygen atom and single-bonded to the other carbon atom and a hydroxyl group (–OH). The other carbon is single-bonded to another oxygen atom (which is in the –OH group) and to three hydrogens. This configuration reflects acetic acid, where the carbonyl (C=O) gives it acidic properties due to the hydrogen in the hydroxyl group.
The arrangement respects the octet rule, and each atom has the correct number of bonds and lone pairs, contributing to the stability of the molecule. This isomer is known for its presence in vinegar and as an important industrial chemical.