Raise the boiling temperature
Answer:

Explanation:
Density is found dividing mass by volume. In this case, we treat krypton as a sphere having a volume of
. Given:


We obtain density of:


This is not a feasible value for a gas like krypton, its radius is actually not 110 pm.
Answer:
They only have one in their valence shell
Explanation:
Answer: (C) Dissolution is the process by which a solute form a solution in a solvent.
Explanation: Dissolution can be described as the process by which a solute dissolves in a solvent to give a solvent.
The solute may be a solid, liquid or gas and solvent is usually a liquid but can also be liquid, gas or supercritical fluid. The most common solvent is water and it is referred to as the universal solvent.
Example are:
1.Stirring of sugar in water.
In this case the solute is the sugar and the solvent is water.
2.Organic substances dissolves readily in solvent like kerosene and benzene and they are known as non-polar solvent while the organic substances are the solute
Answer:
A. H2O
Explanation:
Let us first define the three types of bonds:
1. Nonpolar Covalent: electronegativity difference < 0.4
2. Polar Covalent: electronegativity difference between 0.4 and 1.8
3. Ionic: electronegativity difference > 1.8
This will help us eliminate choices C and D:
-NaCl has a electronegativity difference of 3.0 - 0.9 = 2.1 (ionic bond)
-Cl2 has a electronegativity difference of 3.0 - 3.0 = 0 (nonpolar covalent bond)
However, we still have two more options, A and B, but they are not diatomic for us to use the electronegativity differences with.
We must now consult their geometries. Because CO2 has a linear geometry (O=C=O), the two sides will cancel each other out, resulting in a nonpolar covalent bond. At this point, by process of elimination, we can already determine the answer to be A. H2O. We can verify this by looking at the geometry of H2O, which is bent (H-O-H; imagine the O is above the H's, I cannot draw it in this response). H2O's bent geometry classifies it as polar covalent; the electrons are slightly more attracted towards the O, the more electronegative element. Side note: this makes the O slightly more negative in charge, whilst the H's are slightly more positive in charge.
P.S. I apologize for not being able to draw and demonstrate that last paragraph, but I hope you get a general idea. You can search up the "H2O geometry" and "CO2 geometry" to get a better idea! :)