In basic inorganic chemistry, what is the correct IUPAC name of the ionic compound Li3PO4?

Introduction / Context:
Lithium phosphate, written as Li3PO4, is a simple ionic compound that appears frequently in basic inorganic chemistry and general science examinations. Questions like this test whether the learner can correctly relate a chemical formula to its systematic name using IUPAC style conventions. Being comfortable with naming compounds such as Li3PO4 builds a strong foundation for understanding more complex salts, reactions and stoichiometry problems that follow later in the syllabus.

Given Data / Assumptions:
- The formula of the compound is Li3PO4.
- Lithium is a metal that forms Li+ ions in ionic compounds.
- The phosphate ion is represented by PO4 with an overall charge of 3-.
- Standard IUPAC naming conventions for ionic compounds are assumed.

Concept / Approach:
In ionic compounds, the cation name is written first, followed by the anion name. Lithium forms a monovalent cation Li+. Phosphate is a common polyatomic anion with the formula PO4 and charge 3-. The overall charge balance determines the ratio of ions: three Li+ ions balance one PO4 3- ion to give Li3PO4. For naming, lithium remains simply lithium, while PO4 3- is named phosphate. There is no need to indicate oxidation states for lithium because it almost always has a +1 oxidation state in its compounds.

Step-by-Step Solution:
Step 1: Identify the metal cation in Li3PO4. It is lithium, which forms Li+ ions. Step 2: Identify the non-metal or polyatomic anion. PO4 with a 3- charge is the phosphate ion. Step 3: Check charge balance. Three Li+ ions (total +3) combine with one PO4 3- ion (total -3) to form a neutral compound. Step 4: Apply ionic naming rules. Use the cation name 'lithium' followed by the anion name 'phosphate'. Step 5: Conclude that the correct systematic name for Li3PO4 is lithium phosphate.

Verification / Alternative check:
Another way to verify the name is to recall a short list of common polyatomic ions and their names. For example, NO3 is nitrate, SO4 is sulfate, CO3 is carbonate and PO4 is phosphate. Since PO4 is phosphate, attaching lithium as the metal naturally gives lithium phosphate. Also, there is no need for prefixes or Roman numerals here because the formula already reflects the correct stoichiometric ratio and lithium does not have variable oxidation states in such simple salts. This cross check confirms that the selected name is consistent with standard textbook convention.

Why Other Options Are Wrong:
Option A, lithium perchlorate, would correspond to a formula such as LiClO4, which contains the perchlorate ion, not phosphate. Option B, lithium phyrite, is not a standard or accepted name in basic inorganic chemistry and does not match the PO4 group. Option D, lithium phosphide, would refer to a compound that contains the phosphide ion P3-, with a formula like Li3P, not Li3PO4. Therefore these alternative names do not match the given formula Li3PO4 and are incorrect.

Common Pitfalls:
Learners sometimes confuse phosphate with other polyatomic ions such as sulfate or carbonate, leading to misnaming the compound. Another mistake is to assume that any compound that includes phosphorus must be called phosphide, forgetting that phosphide and phosphate are different species. Students may also think that every compound containing a metal needs a Roman numeral, but this is only required when the metal has multiple common oxidation states, which is not the case for lithium. Keeping a clear mental list of common polyatomic ions helps avoid these errors.

Final Answer:
The correct IUPAC name of Li3PO4 is Lithium phosphate.