Explanation:
As 
is a covalent compound because it is made up by the combination of two non-metal atoms. Atomic number of an iodine atom is 53 and it contains 7 valence electrons as it belongs to group 17 of the periodic table.
Therefore, sharing of electrons will take place when two iodine atoms chemically combine with each other leading to the formation of a covalent bonding.
Hence, weak forces like london dispersion forces will be present between a molecule of .
The weak intermolecular forces which can arise either between nucleus and electrons or between electron-electron are known as dispersion forces. These forces are also known as London dispersion forces and these are temporary in nature.
thus, we can conclude that london dispersion force is the major attractive force that exists among different molecules in the solid.
Answer:
The solutions should be added in this order NaCl > Na2SO4 > Na2S
Explanation:
Silver is insoluble as a chloride, so the silver ions get precipitated on addition of chloride ion as silver chloride. This means Ag+ would be removed the first.
So we will add NaCl in the first step.
The following reaction will occur.
Ag+ + Cl- → AgCl(s)
Both, Pb2 and Ni are soluble as chlorides. (lead chloride is soluble as a hot solution but will ppt when colder).
When we add Na2SO4, Pb2+ will get precipitated (because it's insoluble) as PbSO4 and Ni will remain soluble as NiSO4 is soluble in water.
The reaction that will occur is:
Pb^2+ + SO4^2- → PbSO4(s)
Nickel is insoluble as a sulfide. So when we will add Na2S, nickel will be precipitated as sulfide and be able to separate and be collected.
The solutions should be added in this order NaCl > Na2SO4 > Na2S
