Let's analyze each pair of elements from the table to determine the type of compound they would form, if any, and then write the chemical formula accordingly.
### 1. Sulfur and Chlorine
- Sulfur (S): A non-metal.
- Chlorine (Cl): A non-metal.
When two non-metals combine, they typically form a molecular (covalent) compound. Sulfur can form various chlorides, but a common one is sulfur dichloride (SCl₂).
- Type of compound: Molecular
- Chemical formula: SCl₂
### 2. Xenon and Helium
- Xenon (Xe): A noble gas.
- Helium (He): A noble gas.
Noble gases are generally unwilling to form compounds because they have a complete valence shell. Therefore, xenon and helium will not form a compound.
- Type of compound: Neither
- Chemical formula: None
### 3. Calcium and Sulfur
- Calcium (Ca): A metal.
- Sulfur (S): A non-metal.
A metal and a non-metal typically form an ionic compound. Calcium donates two electrons to sulfur, resulting in the formation of calcium sulfide.
- Type of compound: Ionic
- Chemical formula: CaS
With these analyses in mind, we can fill in the table as follows:
[tex]\[
\begin{tabular}{|c|c|c|c|}
\hline element \#1 & element \#2 & compound formed? & chemical formula \\
\hline sulfur & chlorine & molecular & \text{SCl}_2 \\
\hline xenon & helium & neither & \text{None} \\
\hline calcium & sulfur & ionic & \text{CaS} \\
\hline
\end{tabular}
\][/tex]
