Answer:

Explanation:
According to the ideal gas law equation:

Let's express the number of moles in terms of mass and molar mass:

Let's divide both sides by volume:

Notice that:

So the equation becomes:

Expressing density:

Substituting the given values:

Boyle’s Boyle’s law I believe is correct answer
The number of covalent bonds is determined by the number of valence electrons of an element. The number of electrons tells the maximum number of bonds an element allows. In this case, an oxygen atom requires two bonds. So for Sio2, each oxygen atoms are bonded in double bonds to Si. Hence there are two covalent bonds.
BH3 VSEPR. Boron trihydride structure, BH3. On B, there are three bonded domains and no lone pairs, which give molecular geometries and trigonal planar electron-domain.