Higher <span>C. higher than when the source is stationary</span>
Answer:
D) atomic radii increase from top to bottom of a group
Explanation:
Atomic radii trend along group:
As we move down the group atomic radii increased with increase of atomic number. The addition of electron in next level cause the atomic radii to increased. The hold of nucleus on valance shell become weaker because of shielding of electrons thus size of atom increased.
As the size of atom increases the ionization energy from top to bottom also decreases because it becomes easier to remove the electron because of less nuclear attraction and as more electrons are added the outer electrons becomes more shielded and away from nucleus.
Other options are incorrect because,
A) atomic radii increase from left to right across the period
Correct = atomic radii decreases from left to right across the period
B) ionization energy increases from top to bottom within a family
Correct = ionization energy decreases from top to bottom within a family
C) electronegativity decreases from left to right across a period
Correct = electronegativity increases from left to right across a period
Answer:
Adduct, donate, accept
Explanation:
Lewis acids are those having suitable vacant orbital for electron acceptance and forming a covalent bond with an electron rich species. Example: 
(B has vacant 2p orbital for electron acceptance)
Lewis bases are those having energetically available unshared electrons that can be donated to an electron deficient species and form a covalent bond. Example: 
(N has energetically available lone pair)
So, product of Lewis acid-base reaction is an adduct (
) where a new covalent bond is formed between B and N.
