Answer:
It is trigonal planer b/c the structure has 3 bonded pairs of electrons and 0 nonbonded pairs.
Step-by-step explanation:
Valence no. = 1Ga + 3F = 1(3) + 3(7) = 24 valence electrons
Substrate no. = 3F = 3(8) = 24 electrons in bonds
No. of nonbonded pairs of electrons = V - S / 2 = 24 -24 / 2 = 0
Bonded Pairs of electrons = 3 (3 substrates attached by covalent bonds to central element of compound)
Parent structure = Non bonded Prs + Bonded Prs = 0+ 3 = 3
Therefore parent structure and geometry are based on an AX₃ configuration which is trigonal planer.