How is SiO2 polar?

[Maria1E]

Don't its dipole moments cancel out?

[Troy Tavangar 1I]

SiO2 should be nonpolar I believe. Are you thinking of SO2 which is polar?

[Maria1E]

No, this was a question on the midterm and I put that it was polar and got it right. But I'm not exactly sure what makes it polar.

[Kyle Alves 3K]

It might be one of those "you should just know" pieces of information: SiO2 can't exist as a molecule by itself, Si has to be connected to two other oxygens atoms to make a covalent network, rather than just being a molecule by itself. Although it makes a nonpolar molecule overall, the SiO2 becomes polar. At least thats what I could find online