Question 10 Gabriel Final Review

[Ariel Lucas 1H]

Hi! I was looking at the Final Review for Gabriel's UA session and was wondering why for question 10, SiH4 is not considered a molecule with polar covalent bonds that have dipole moments that cancel out making it nonpolar overall? I thought that there was unequal sharing of electrons between the Si and H bond due to electronegativity. Thank you!

[gary_vernes]

Since Si is the central atom and is more electronegative than H, the dipole moment will be going towards Si. Since they are all going towards Si, it does not cancel out.