Number of stereoisomers possible for the complexes, $[\ce{CrCl3(py)3}]$ and $[\ce{CrCl3(ox)2}]^{3-}$ are respectively

( $py$ = pyridine, $ox$ = oxalate)

Question

Number of stereoisomers possible for the complexes, [CrCl3(py)3] and [CrCl3(ox)2]3- are respectively (py = pyridine, ox = oxalate)

Paaras Thakur · Accepted Answer

2 & 3. 🧠 Compute Stereoisomer Counts Stereoisomer = geometric + optical (enantiomers count separately). 🗺️ (a) [CrCl3(py)3] — Type MA3 B3 Octahedral MA3 B3 → fac (3 like ligands on one face) and mer (3 like ligands on a meridian). Both fac and mer are achiral (each has a mirror plane). Stereoisomer count = 2. 🗺️ (b) [CrCl2(ox)2]3- — Type [M(AA)2 B2] (Note: the formula in the question is keyed as 3 Cl + 2 ox, which exceeds 6 donors; the chemistry-consistent reading is [CrCl2(ox)2]3-, type [M(AA)2 B2].) - trans isomer: Cl axial-axial (180°), achiral. Count = 1. - cis isomer: Cl cis (90°), chiral → 2 enantiomers (Δ, Λ). Count = 2. Stereoisomer count = 1 + 2 = 3. 🗺️ Final (a) 2 ; (b) 3. ⚡ Stereoisomer Counting Summary | Type | Geometric | Optical | Total stereoisomers | |---|---|---|---| | MA3 B3 (oct) | fac, mer | none | 2 | | M(AA)2 X2 (oct) | cis (chiral), trans | cis Δ/Λ | 3 | | M(AA)3 | one form | Δ/Λ | 2 | ⚠️ cis-M(AA)2 X2 Counted as Δ + Λ cis form is chiral, contributing 2 enantiomers. trans is achiral, contributing 1. Total = 3. Answer: (3) 2 and 3

Answer

3 & 3

Answer

2 & 2

Answer

2 & 3

Answer

1 & 2

Number of stereoisomers possible for the complexes, [CrCl3(py)3] and [CrCl3(ox)2]3- are respectively (py = pyridine, ox…

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