Questions: If atoms with the electron-dot symbols shown below are combined, what is the formula of the onic compound that is formed? X · Ÿ.

Solution Steps

The electron-dot symbols represent the valence electrons of the atoms involved. In this case, we have:

• Atom \( \mathrm{X} \) with one dot, indicating it has one valence electron.
• Atom \( \mathrm{Y} \) with two dots, indicating it has two valence electrons.

Atoms form ionic compounds by transferring electrons to achieve a full outer shell.

• Atom \( \mathrm{X} \) likely needs to lose one electron to achieve a stable electron configuration, suggesting it forms a \( +1 \) ion.
• Atom \( \mathrm{Y} \) likely needs to gain two electrons to achieve a stable electron configuration, suggesting it forms a \( -2 \) ion.

To balance the charges in the ionic compound:

• Two \( \mathrm{X} \) atoms, each with a \( +1 \) charge, are needed to balance the \( -2 \) charge of one \( \mathrm{Y} \) atom.

Thus, the formula of the ionic compound is \( \mathrm{X}_2\mathrm{Y} \).

Final Answer