Molecular formula Name of compound XeO2 XeF2 SeS2 Se4S4 Ni

The Correct Answer and Explanation is:
Here are the correct names for the molecular formulas listed:
| Molecular Formula | Name of Compound |
|---|---|
| XeO₃ | Xenon trioxide |
| XeF₆ | Xenon hexafluoride |
| SeS₂ | Selenium disulfide |
| Se₄S₄ | Tetraselenium tetrasulfide |
| NH₃ | Ammonia |
Explanation
The naming of chemical compounds follows IUPAC (International Union of Pure and Applied Chemistry) rules, which provide systematic guidelines based on the elements involved and their quantities.
1. XeO₃ – Xenon trioxide
Xenon (Xe) is a noble gas that can form compounds under special conditions. In XeO₃, xenon is bonded to three oxygen atoms. Since oxygen is more electronegative, it is named as “oxide”. The prefix “tri-” is used for three oxygen atoms. Thus, the name is xenon trioxide.
2. XeF₆ – Xenon hexafluoride
This is a binary compound of xenon and fluorine. Xenon forms six bonds with fluorine atoms. The prefix “hexa-” denotes six. Fluorine, being more electronegative, comes second in naming. Therefore, the compound is xenon hexafluoride.
3. SeS₂ – Selenium disulfide
This compound consists of selenium and two sulfur atoms. It’s named using prefixes: no prefix for the first element (unless there’s ambiguity) and “di-” for two sulfur atoms. Hence, the name is selenium disulfide.
4. Se₄S₄ – Tetraselenium tetrasulfide
Both selenium and sulfur appear four times each. Because this compound is a molecular (non-metal) compound, we use the appropriate prefixes: “tetra-” for four. Hence, tetraselenium tetrasulfide is correct.
5. NH₃ – Ammonia
Although its formula suggests a systematic name like nitrogen trihydride, NH₃ is commonly known as ammonia. This is a well-established common name and is universally accepted in chemical contexts.
These naming conventions help chemists communicate chemical compositions clearly and consistently across languages and disciplines.
