On the basis of VSEPR theory, predict the shapes of the following molecules molecules /ions ?
`(i)SiF_(4) (ii) NH_(2)^(-) (iii) NH_(4)^(+) (iv) C_(2) H_(2) (v) H_(3)O^(+) (vi) F_(2)O (vii) PCl_(3) (viii) PF_(5)`.

Explanation

To predict the shapes of the given molecules/ions based on VSEPR (Valence Shell Electron Pair Repulsion) theory, we will analyze the number of bonding pairs and lone pairs of electrons around the central atom for each molecule/ion.

### Step-by-Step Solutions:

1. **SiF₄ (Silicon Tetrafluoride)**
- Silicon (Si) has 4 valence electrons.
- It forms 4 single bonds with 4 fluorine atoms.
- There are no lone pairs on the silicon atom.
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