Question

click on the best lewis structure for xef₃⁺?
diagrams of four lewis structures for xef₃⁺ are shown

Explanation:

Step1: Recall Lewis Structure Rules

Lewis structures show valence electrons, with atoms satisfying octet (or duet for H, expanded octet for period 3+). Fluorine (F) needs 8 electrons (7 valence, gains 1; in bonds, 2 per bond + lone pairs). Xenon (Xe) can have expanded octet.

Step2: Calculate Valence Electrons

For $\ce{XeF3^+}$: Xe (8) + 3×F (7) - 1 (positive charge) = 8 + 21 - 1 = 28 valence electrons.

Step3: Analyze Each Structure

• Top - Left: Xe bonded to 3 F (single bonds: 3×2=6 electrons). Each F has 6 lone pairs (3×6=18). Xe has 2 lone pairs (4). Total: 6 + 18 + 4 = 28. F has 8 (2 bond + 6 lone), Xe has 8 (3 bonds + 2 lone pairs, expanded octet okay).
• Top - Right: F has no lone pairs (violates octet: 2 bond electrons only, needs 6 more). Invalid.
• Bottom - Left: Double bonds (Xe=F). F with double bond would have 6 electrons (4 bond + 2 lone? No, F should have single bonds (needs 1 bond, 6 lone). Double bonds on F are incorrect (F is halogen, rarely double bonds, and valence electrons here would not match).
• Bottom - Right: Xe bonded to 2 F (single bonds: 2×2=4) and 1 F? Wait, structure shows two F with lone pairs, one F? No, count: two F (2×2 bond + 6 lone: 2×8=16), one F (2 bond + 6 lone: 8), Xe: 2 bonds? Wait, no, the structure has two F with lone pairs and one F? Wait, no, the bottom - right has two F (dots) and one F? Wait, no, recalculating: bottom - right: two F (each 2 bond + 6 lone: 8 each), one F (2 bond + 6 lone: 8), Xe: 3 bonds? Wait, no, the structure is $\ce{[:F - Xe - F:][:F:]^+}$? Wait, no, the drawing: bottom - right has two F with dots (lone pairs) and one F with dots? Wait, no, earlier count for top - left was correct. Top - left has 3 F (each 6 lone, 2 bond), Xe 2 lone pairs. Total 28. Other structures fail octet (top - right: F has no lone pairs) or incorrect bonding (bottom - left: F double bonds).

Answer:

The Top - Left Lewis Structure (the first structure with three F atoms each having six lone pair electrons and Xe with two lone pair electrons, all in brackets with a + charge)