Answer : C) separate the parts by their properties.
Explanation:
Mixture is a substance which has two or more components which do not combine chemically and do not have any fixed ratio in which they are present. Trail is a mixture of various substances which do not react chemically and thus the constituents retain their chemical properties. The substances can be separated by using physical properties.
Compound is a pure substance which is made from atoms of different elements combined together in a fixed ratio by mass.It can be decomposed into simpler constituents using chemical reactions. The elements lose their individual chemical properties. The elements can not be separated using physical means.
N=9.03 x 10^ 23/6.02 x 10^23
n= 1.5 Mol
four covalent bonds in SiO2