Whenever objects are placed in a line with spaced in between them, the number of spaces is one less than the number of objects. For reference, you may hold up four fingers and count the spaced between your fingers.
Therefore, if there are 105 molecules, then there are 104 spaces present.
We also know that 1 mm = 1000 nm. So, we first convert the spacing to millimeters as the final answer is required in millimeters
spacing = 10.59/1000 = 0.01059 mm
Now, the width of the lattice will be (ignoring the size of the molecules):
104 * 0.01059
1.10 millimeters
There are three significant figures, this is because the zero before the decimal does not count
2 Fluorine atoms covalently bonded with each other, each sharing an equal number of a single, one valence electron to achieve a stable octet, would form a diatonic fluorine gas. It is a diatomic molecule, a molecule consisting of 2 atoms that are the same, in this case fluorine.
