What Would Be The Structure Predicted By Using Lewis Dot Structures For Calcium Phosphide? CaP CaP_2 Ca_2P Ca_2P_2 Ca_3P_2
What would be the structure predicted by using Lewis dot structures for calcium phosphide CaP CaP2 Ca2P Ca2P2 Ca3P2
The Correct Answer and Explanation is:
The correct formula for calcium phosphide based on Lewis dot structure predictions and known ionic bonding behavior is Ca₃P₂.
Explanation
To predict the structure of calcium phosphide using Lewis dot structures, we must analyze the typical electron behavior of calcium (Ca) and phosphorus (P) atoms:
- Calcium (Ca) is a Group 2 alkaline earth metal, which means it has 2 valence electrons. Calcium readily loses 2 electrons to achieve a stable noble gas configuration (like Argon), forming a Ca²⁺ ion.
- Phosphorus (P) is a Group 15 nonmetal, with 5 valence electrons. It gains 3 electrons to complete its octet, forming a P³⁻ ion.
Since Ca wants to lose 2 electrons (Ca²⁺) and P wants to gain 3 electrons (P³⁻), we need to balance the total charges of the ions to form a neutral compound.
To balance charges:
- 3 Ca²⁺ ions contribute a total of +6 charge.
- 2 P³⁻ ions contribute a total of –6 charge.
Thus, the simplest ratio that results in a neutral compound is: 3 Ca2++2 P3−→Ca3P2\text{3 Ca}^{2+} + \text{2 P}^{3-} \rightarrow \text{Ca}_3\text{P}_2
This gives the empirical formula Ca₃P₂, which is the correct ionic compound formed between calcium and phosphorus. The Lewis dot structure would show:
- Each calcium atom losing two electrons (becoming Ca²⁺).
- Each phosphorus atom gaining three electrons (becoming P³⁻).
This results in an ionic lattice structure, where the Ca²⁺ and P³⁻ ions are held together by strong electrostatic forces, not by shared electrons (as in covalent bonds), consistent with ionic bonding in salts.
Therefore, among the options (CaP, CaP₂, Ca₂P, Ca₂P₂, Ca₃P₂), Ca₃P₂ is the only formula that correctly represents the charge balance based on Lewis structure predictions.
