\begin{tabular}{|c|c|c|c|}
\hline
Compound & \begin{tabular}{c}
Melting \\
point \\
[tex]$\left({ }^{\circ} C \right)$[/tex]
\end{tabular} & \begin{tabular}{c}
Boiling \\
point \\
[tex]$\left({ }^{\circ} C \right)$[/tex]
\end{tabular} & \begin{tabular}{c}
Conducts \\
electricity
\end{tabular} \\
\hline
A & -183 & -164 & no \\
\hline
B & 660 & 2,467 & yes \\
\hline
C & 772 & 1,600 & yes \\
\hline
\end{tabular}

Which compound is most likely a covalent compound? [tex]$\square$[/tex]



Answer :

To determine which of the given compounds is most likely a covalent compound, let's review the key characteristics of covalent compounds:

1. Covalent compounds generally have low melting points.
2. Covalent compounds generally have low boiling points.
3. Covalent compounds do not conduct electricity in solid or liquid form because they do not have free-moving charged particles.

Given the data in the table:

- Compound A:
- Melting point: -183°C
- Boiling point: -164°C
- Conducts electricity: No

- Compound B:
- Melting point: 660°C
- Boiling point: 2467°C
- Conducts electricity: Yes

- Compound C:
- Melting point: 772°C
- Boiling point: 1600°C
- Conducts electricity: Yes

### Analysis

1. Melting and Boiling Points:
- Compound A has very low melting and boiling points (-183°C and -164°C, respectively), which aligns with the characteristic of covalent compounds.
- Compound B has a relatively high melting point (660°C) and an extremely high boiling point (2467°C), which is not typical for covalent compounds.
- Compound C also has high melting and boiling points (772°C and 1600°C, respectively), which again is not typical for covalent compounds.

2. Conductivity:
- Compound A does not conduct electricity, in line with what we expect for a covalent compound.
- Compound B conducts electricity, indicating the presence of free-moving charged particles, which is not a feature of covalent compounds.
- Compound C also conducts electricity, which again is not a property of covalent compounds.

Based on the characteristics and the data provided, Compound A exhibits all the properties of a typical covalent compound: low melting point, low boiling point, and does not conduct electricity.

Therefore, the most likely covalent compound is:
[tex]\[ \boxed{A} \][/tex]