CBr4 is called tetrabromomethane. First we need to count the total number of valence electrons. We just add the valence electrons of each atom involved.
C = 4
Br = 7 x 4
Next, we have to assign the central atom; In this case it is C.
Now we have to connect the atoms and form a bond. We can form four C-Br bonds.
Br- C - Br
Finally, we have to distribute The remaining electrons on Br provided that it follows the octet rule.
CBr4 is similar with methane (CH4) in terms of geometry. It's predicted bond angle is about 110 degrees. The effect of C-Br bonds cancels since the molecule is symmetric. Therefore it is a non-polar molecule.