Valence Electrons and Ionic Compounds

The video tutorial explains how to write the Lewis structure for potassium sulfide (K2S). It begins by introducing the concept of ionic compounds, where electrons are transferred from a metal to a non-metal. The tutorial details the valence electrons of potassium and sulfur, explaining how potassium transfers its electron to sulfur, resulting in ionic charges. The video concludes by illustrating the Lewis structure and explaining the concept of a formula unit in a crystal lattice.

What type of compound is formed when a metal and a nonmetal combine?

• Ionic compound

• Covalent compound

• Metallic compound

• Molecular compound

How many valence electrons does potassium have?

• Three

• Four

• Two

• One

In which group is sulfur found on the periodic table?

• Group 1

• Group 18

• Group 2

• Group 16

What charge does a potassium ion have after losing an electron?

• 1+

• 2+

• 1-

• 2-

How many electrons does sulfur gain to achieve a stable electron configuration?

• Two

• Three

• Four

• One

What is the charge on the sulfide ion after gaining electrons?

• 1+

• 2+

• 1-

• 2-

What is a formula unit in the context of ionic compounds?

• A single molecule

• A repeating pattern of ions

• A metallic bond

• A covalent bond

Why are brackets used around the sulfide ion in the Lewis structure?

• To show the ion's charge

• To denote a molecular structure

• To highlight the metal

• To indicate a covalent bond