Final answer:
To predict if a compound is ionic or covalent, one must look at the elements involved, using their positions on the periodic table. Metals and nonmetals typically form ionic compounds, whereas nonmetals tend to form covalent compounds. The periodic table can help identify the likely charge and the type of ions present in ionic compounds.
Step-by-step explanation:
To determine if a compound is ionic or covalent, you should first look at the types of atoms involved. Ionic compounds are generally formed when metals transfer electrons to nonmetals, resulting in positive and negative ions held together by ionic bonds. Covalent compounds are formed when nonmetals share electrons in a bond. Metallic bonds occur between metal atoms.
Use of Periodic Table to Predict Compound Type
Analyze the position of the elements in the periodic table to predict whether a compound is ionic or covalent. For example:
- SO2: This is a covalent compound because it consists of nonmetals sulfur and oxygen.
- CaF2: This is an ionic compound with the ions Ca2+ and F- because it consists of the metal calcium and the nonmetal fluorine.
- N₂H4: This is a covalent compound, composed purely of nonmetals (nitrogen and hydrogen).
- Al2(SO4)3: This is an ionic compound featuring the ions Al3+ and SO42-, as it includes the metal aluminum and the polyatomic ion sulfate.
Tip: Metals are generally located to the left of the staircase line on the periodic table, and nonmetals to the right. Metals tend to form cations (+), while nonmetals tend to form anions (-) in ionic compounds.