Draw the structures of the following: (i) XeF4 (ii) HClO4

(i) XeF4:

Xenon tetrafluoride (XeF4) has a square planar geometry. Xenon is the central atom, and it has 8 valence electrons. Four of these electrons are used to form bonds with four fluorine atoms. The remaining four electrons exist as two lone pairs. According to VSEPR theory, the two lone pairs occupy positions that maximize their distance from each other and from the bonding pairs. This arrangement leads to a square planar structure.

[Diagram of XeF4 showing Xenon in the center with four Fluorine atoms at the corners of a square and two lone pairs above and below the plane]

(ii) HClO4:

Perchloric acid (HClO4) has a tetrahedral structure. Chlorine is the central atom, and it is surrounded by four oxygen atoms. One oxygen atom is bonded to chlorine via a single bond and also to a hydrogen atom, forming the –OH group. The other three oxygen atoms are bonded to chlorine via double bonds. The chlorine atom has an expanded octet, which is possible for elements in the third period and beyond.

[Diagram of HClO4 showing Chlorine in the center with one OH group and three double-bonded Oxygen atoms. The overall shape is tetrahedral.]