Question

question 4 (2 points)
consider the oxalate ion, c₂o₄⁻².
the lewis structure has 1 central atoms.
each central atom has 2 single bonds and one double bond.
the number of reds at each central atom is 2.
the bond angles are 3° and the shape at each central atom is 4.
c₂o₄⁻² is a 5 symmetrical/asymmetrical molecule.
a. 0 b. 1 c. 2 d. 3 e. 4 f. 180 g. 90 h.
120
i. 109.5 j. diatomic k. linear l. planar trigonal m. bent
n. pyramidal o. tetrahedral p. symmetrical q. asymmetrical

Explanation:

• Central atoms: In \(C_2O_4^{2 -}\), there are two carbon atoms (\(C\)) which act as central atoms.
• REDs (Region of Electron Density): Each central \(C\) atom has 2 single bonds and 1 double bond. The number of REDs is \(3\) (a single bond is one RED and a double bond is also one RED).
• Bond angles: For a central atom with 3 REDs (trigonal planar electron - pair geometry), the bond angle is \(120^{\circ}\).
• Shape at central atom: With 3 REDs and no lone pairs on the central \(C\) atom (since all electron - pairs are in bonds), the molecular shape is planar trigonal.
• Symmetry: The \(C_2O_4^{2 -}\) ion has a symmetrical structure.

Answer:

1. C. 2
2. D. 3
3. H. 120
4. L. planar trigonal
5. P. symmetrical