Final Answer:
a. Nitrogen belongs to group 15 of the periodic table and has 5 valence electrons.
b. Lithium belongs to group 1 of the periodic table and has 1 valence electron.
c. Phosphorus belongs to group 15 of the periodic table and has 5 valence electrons.
d. Barium belongs to group 2 of the periodic table and has 2 valence electrons.
e. Bromine belongs to group 17 of the periodic table and has 7 valence electrons.
f. Carbon belongs to group 14 of the periodic table and has 4 valence electrons.
Step-by-step explanation:
a. Nitrogen, positioned in group 15, features an atomic number of 7, indicating the number of electrons. To determine valence electrons, we refer to the group number, which matches the number of valence electrons for main group elements. Nitrogen falls within group 15, therefore possessing 5 valence electrons.
b. Lithium resides in group 1, also known as the alkali metals. Elements in this group contain 1 valence electron, consistent with their group number. Lithium, with an atomic number of 3, falls in this category, possessing 1 valence electron.
c. Phosphorus, a member of group 15, aligns with its group number in the periodic table. With an atomic number of 15, phosphorus bears 5 valence electrons, as shared by other elements in the same group.
d. Barium is categorized within group 2, also recognized as the alkaline earth metals. Being in group 2, it has 2 valence electrons, as consistent with elements within this category. Barium, with an atomic number of 56, conforms to this rule.
e. Bromine, positioned in group 17 or the halogens, contains 7 valence electrons. As an element in group 17, bromine possesses 7 valence electrons, matching its group number and fulfilling the octet rule for stability.
f. Carbon belongs to group 14, characterized by having 4 valence electrons. With an atomic number of 6, carbon falls within this group, maintaining 4 valence electrons, essential for its bonding behavior and stability in compounds.