Answer:
Explanation: The strengths of the inter molecular forces varies as follows -

The normal boiling point of CSe2 is 125°C and that of CS2 is 116°C, which explains the trend that as we move down the group, the boiling point of e compound increases as the size increases.
This usually happens because larger and heavier atoms have a tendency to exhibit greater inter molecular strengths due to the increase in size . As the size increases, the valence shell electrons move far away from the nucleus, thus has a greater tendency to attract the temporary dipoles.
And larger the inter molecular forces, more tightly the electrons will be held to each other and thus more thermal energy would be required to break the bonds between them.
<span>Specific gravity is the ratio of the density of a substance to the density of a reference substance; equivalently, it is the ratio of the mass of a substance to the mass of a reference substance for the same given volume.</span>
Electrons group themselves in pairs in their energy levels. To calculate the number of electrons allowed in any energy level, find the square of the number representing the energy level and multiply it by two. Using this formula, atoms can have two electrons in their first energy level, eight in the second, and eighteen in their third. The quantity of electrons at each level grows as the number of the energy level increases.
The answer is c because the calculations for the elements have to connect with the compounds
Answer:
812.754 miles
Why:
0.621371 miles per km