Answer:
Ion-dipole forces
Explanation:
Na⁺ is a cation, that is, an ion with a positive charge.
NH₃ has polar covalent bonds (due to the difference in electronegativity between nitrogen and hydrogen). According to the VESPR theory, it has a trigonal pyramidal shape with a lone pair. As a consequence, it has a net dipole moment and the molecule is polar.
The intermolecular forces between Na⁺ (ion) and NH₃ (dipole) are ion-dipole forces.
A gene is the basic unit of heredity, DNA a self replicating material and chromosome a structure of nucleic acids and protein.
The answer is hydrogen. the first element in the periodic table.
Density as you should know is equal to mass/volume. Solve for the volume.
Now, you know that you are dealing with a sphere. You know the volume of a sphere is V= 4/3pi r ^3.
You know the volume so just solve for r