Answer:
1,1-Dichloroethene (CH₂CCl₂) and Ethene (H₂CCH₂) have same molecular geometries.
Step-by-step explanation:
The molecular geometries of all molecules are drawn below. Among these molecules four molecules contains four atoms which has same geometry. These are Boron in BF₃, Carbon in CH₂O, both carbon atoms CH₂CCl₂ and both carbon atoms H₂CCH₂. All specified elements in these molecules have same geometry (Trigonal Planar).
While, the overall geometry of only two molecules is same. Those two are CH₂CCl₂ and H₂CCH₂ because in these molecules all carbon atoms have Trigonal Planar Geometry. Hence, we can confirm that among given compounds this pair has same geometry.