Which of the following are ionic, and which are molecular? (d) Ca(NO₃)₂

Verified step by step guidance

1. Identify the types of elements involved in the compound Ca(NO_3)_2.
2. Recognize that calcium (Ca) is a metal and nitrate (NO_3) is a polyatomic ion.
3. Recall that ionic compounds are typically formed between metals and nonmetals or polyatomic ions.
4. Determine that Ca(NO_3)_2 is an ionic compound because it consists of a metal (Ca) and a polyatomic ion (NO_3).
5. Conclude that Ca(NO_3)_2 is ionic based on the presence of a metal and a polyatomic ion.

Key Concepts

Ionic Compounds

Ionic compounds are formed when atoms transfer electrons, resulting in the formation of charged ions. These compounds typically consist of a metal and a non-metal, where the metal donates electrons to become a positively charged cation, and the non-metal accepts electrons to become a negatively charged anion. The electrostatic attraction between these oppositely charged ions results in a stable ionic lattice structure.

Molecular Compounds

Molecular compounds are formed when two or more non-metal atoms share electrons through covalent bonds. Unlike ionic compounds, they do not consist of ions but rather discrete molecules. These compounds often have lower melting and boiling points compared to ionic compounds and can exist in various states (solid, liquid, gas) at room temperature.

Nitrate Ion

The nitrate ion (NO3-) is a polyatomic ion commonly found in ionic compounds. It consists of one nitrogen atom covalently bonded to three oxygen atoms, with an overall negative charge. In the context of the compound Ca(NO3)2, calcium (Ca) acts as a cation, while the nitrate ions serve as anions, illustrating the formation of an ionic compound through the combination of these charged species.