How many of the following molecules are polar?

Question

SiSe2

SI4

XeF4

CCl4

Answer 1

If you are to draw the Lewis dot structures for each of the mentioned compounds you'd find the following geometries.

SiSe₂ would be linear thus non-polar.

SI₄ Sulfur being able to expand its octet would take on a seesaw geometry and would be polar.

XeF₄ Xenon also able to expand its octet would take on a square planar geometry and would be non-polar.

CCl₄ This molecule would take on a tetrahedral geometry and would be non-polar.

Thus one of the listed molecules are polar.

I hope this helps!