Answer:
Ionization energy is the energy required to remove an electron from a specific atom. It is measured in kJ/mol, which is an energy unit, much like calories. The ionization energies associated with some elements are described in the Table 1. For any given atom, the outermost valence electrons will have lower ionization energies than the inner-shell kernel electrons. As more electrons are added to a nucleus, the outer electrons become shielded from the nucleus by the inner shell electrons. This is called electron shielding .
Explanation:
a little summary
Ionization energy refers to the amount of energy needed to remove an electron from an atom.
Ionization energy decreases as we go down a group.
Ionization energy increases from left to right across the periodic table.
Answer:
Paraffin oil is used for determination of boiling point and melting point for the following reasons: It has a very high boiling point and so it can be used to maintain high temperatures in the boiling and melting point apparatus without loss of the substance.
Water can exist in three states.
1) Solid State: Called Ice.
2) Liquid State: Called Liquid Water.
3) Gas State: Called Steam.
Remember:
The physical states of a matter depends upon the interactions between the particles of that substance. The interactions are very strong in solid state, strong in liquid state and very weak or negligible in gas state.
If you want to change the state from solid to liquid, or from liquid to gas you will have to provide energy in order to break the interactions between the molecules. Stronger the interactions, the more is energy required to break the interactions.
Water need more energy to convert from liquid to gas phase because hydrogen bond interactions are present among the molecules of water. And the hydrogen bonds are strong enough. Hence in order to break these interactions high energy is required.
Unit Cell is the basic <span>repeating structural unit of a crystalline solid .</span>
