Question 5.1: Draw Lewis structures for the simplest binary compounds that......
Draw Lewis structures for the simplest binary compounds that can be formed from the following pairs of nonmetals.
a. Nitrogen and iodine b. Sulfur and hydrogen
a. Nitrogen is in Group VA of the periodic table and has five valence electrons. It will need to form three covalent bonds to achieve an octet of electrons. Iodine, in Group VIIA of the periodic table, has seven valence electrons and will need to form only one covalent bond in order to have an octet of electrons. Therefore, three iodine atoms will be needed to meet the needs of one nitrogen atom. The Lewis structure for this molecule is
Each atom in NI_{3} has an octet of electrons; these octets are circled in color in the following diagram.
b. Sulfur has six valence electrons and hydrogen has one valence electron. Thus, sulfur will form two covalent bonds (6 + 2 = 8), and hydrogen will form one covalent bond (1 + 1 = 2). Remember that for hydrogen, an “octet” is two electrons; the noble gas that hydrogen mimics is helium, which has only two valence electrons.
