Determine the Oxidation States of Various Compounds

To determine the oxidation states of different compounds, we must consider the common oxidation states of the elements in those compounds and apply the rules of oxidation states. Below we will analyze each compound individually:

• a) NaI
  In sodium iodide (NaI), sodium (Na) has an oxidation state of +1 and iodine (I) has an oxidation state of -1. Therefore, the oxidation states are Na: +1, I: -1.
• b) GdCl₃
  In gadolinium chloride (GdCl₃), gadolinium (Gd) is usually +3, and each chlorine (Cl) atom has an oxidation state of -1. Hence, the oxidation states are Gd: +3, Cl: -1.
• c) LiNO₃
  In lithium nitrate (LiNO₃), lithium (Li) has an oxidation state of +1. Nitrogen (N) in nitrate typically has an oxidation state of +5, while each oxygen (O) has an oxidation state of -2. Thus, we find Li: +1, N: +5, O: -2.
• d) H₂Se
  In hydrogen selenide (H₂Se), each hydrogen (H) atom has an oxidation state of +1, while selenium (Se) has an oxidation state of -2. Consequently, the oxidation states are H: +1, Se: -2.
• e) Mg₂Si
  In magnesium silicide (Mg₂Si), magnesium (Mg) typically has an oxidation state of +2, while silicon (Si) in this compound is considered to be at an oxidation state of -4 overall (as it balances with two magnesium atoms). Therefore, Mg: +2, Si: -4.
• f) RbO₂
  In rubidium dioxide (RbO₂), rubidium (Rb) has an oxidation state of +1, while each oxygen (O) is generally -1 in peroxides. Hence, the oxidation states are Rb: +1, O: -1.
• g) HF
  In hydrofluoric acid (HF), hydrogen (H) has an oxidation state of +1 and fluorine (F) has an oxidation state of -1. Therefore, the oxidation states are H: +1, F: -1.

Understanding these oxidation states is crucial for analyzing chemical reactions and bonding in these compounds.