Final answer:
c) A solid line. The atoms in a covalent compound are connected with a solid line representing the sharing of a pair of electrons, which is known as a covalent bond.
Step-by-step explanation:
When two atoms come together to form a covalent compound, we connect the two atoms with a solid line. This line represents a covalent bond, which is formed when atoms share a pair of electrons.
An example of such bonding can be seen in the hydrogen molecule H2, where we depict the bond between the hydrogen atoms as a single line connecting the two, such as H-H.
This shared pair of electrons constitutes a single covalent bond, which is crucial for many molecules to achieve a full octet and attain chemical stability, except in cases like helium and hydrogen.
Atoms in a molecule can be of the same element, forming substances like molecular hydrogen (H2), or they can be of different elements, forming covalent compounds.
For instance, a water molecule (H2O) is a common example of a covalent compound, where each hydrogen atom is connected to the oxygen atom by a single solid line, representing the covalent bonds that hold the molecule together.
The covalent bond is usually represented by a single line between the bonded atoms, e.g., the H₂ molecule shown in the above equation is generally shown as H-H. An example is a reaction between hydrogen having one valence electron and carbon having four valence electrons react to form CH4 molecule.