Answer:
(a) Covalent bond. NF₃ (nitrogen trifluoride)
(b) Ionic bond. LiCl (lithium chloride)
Explanation:
<em>(a) N and F</em>
Nitrogen and fluorine are nonmetals, with high and similar electronegativities, so they form covalent bonds, in which they share pairs of electrons to complete the octet in their valence shell. N has 5 valence electrons so it will form 3 covalent bonds while each Cl has 7 valence electrons so it will form 1 covalent bond. As a result, the empirical formula is NF₃ (nitrogen trifluoride).
<em>(b) Li and Cl</em>
Lithium is a metal and Chlorine is a nonmetal. They have different electronegativities so they form an ionic bond, in which Cl gains 1 electron (7 valence e⁻) and Li loses 1 electron (1 valence e⁻). The empirical formula is LiCl (lithium chloride).
Electron affinity is the energy released when an electron is accepted by a neutral atom forming a negative ion. Chlorine has the higher electron affinity because it readily accepts an electron to become more stable. On the other hand, sodium have to give up an electron to complete its valence shell.
To Earth, since it has the same radio and masses. This is what I believe.
