Could you add a picture of the question ?
Answer:
c because they are the closest together
Answer:
There are 8 electrons in the last level. Because of the octet rule.
Answer: Homogeneous mixture
Explanation:
Element: It is a substance made up from only one type of atom. It is not a mixture.
Heterogeneous mixture: This is a mixture having two or more substances that are unevenly distributed. The substances can be easily separated.
Homogeneous mixture: This is a mixture having two or more substances that are evenly distributed. These cannot be easily separated. The substances retain their original properties.
Compound: It is a substance which is composed of two or more elements in a specific ratio. these are evenly distributed but in this the elements do not retain their original properties.
Hence, from the above points, it is easily justified that homogeneous mixtures are the ones, where the particles are evenly distributed and also retain their original properties.