Student Exploration: Covalent Bonds
Directions: Follow the instructions to go through the simulation. Respond to the questions and
prompts in the orange boxes.
Vocabulary: covalent bond, diatomic molecule, Lewis diagram, molecule, noble gases, nonmetal, octet rule,
shell, valence, valence electron
Prior Knowledge Questions (Do these BEFORE using the Gizmo.)
1. There are eight markers in a full set, but Flora and Frank each only have seven markers. Flora is missing
the red marker, and Frank is missing the blue marker.
What can they do so that each has a full set of markers?
borrow from another set
2. Otto and Olivia each have six markers. Otto is missing the purple and green markers, and Olivia is missing
the black and brown markers. What can they do so that each has a full set?
give each other the markers they need
Gizmo Warm-up
Just like the students described above, nonmetal atoms can share
electrons.As you will see in the Covalent Bonds Gizmo, atoms form
bonds in this way.
To begin, check that Fluorine is selected from the Select a
substance menu. Click Play ( ) to see the electrons orbiting the
nucleus of each atom.
1. The outermost electrons in each atom are called valence electrons. How many valence electrons does
each fluorine atom have? 7
2. Click Pause ( ). Drag a valence electron from the left atom to the right atom. Click Play.
What happens? they share the atom on the new shell
3. Click Pause, drag a valence electron from the right atom to the left, and then click Play.
What happens now? 2 electrons orbit the atoms
Reproduction for educational use only. Public sharing or posting prohibited. © 2020 ExploreLearning™ All rights reserved
, Activity A: Get the Gizmo ready:
● Click Reset.
Sharing electrons ● Select Hydrogen.
Introduction: The electrons that orbit the nucleus of an atom are arranged into shells. The first shell contains
up to two electrons and the second contains up to eight electrons. Most elements are stable when they have
eight valence electrons—a rule of thumb known as the octet rule. (Elements with less than five electrons are
stable with two valence electrons.)
Question: What happens when atoms share electrons?
1. Predict: Each hydrogen atom has one valence electron, but it needs two electrons to be stable. How can
both hydrogen atoms each achieve a stable configuration?
Since they both need two to achieve a stable configuration, the remaining electrons can bond to one
another so each atom shares them.
2. Form a bond: Drag the electrons so that they move around both hydrogen atoms. Click Play to observe
them in orbit, and then click Check. You have created a covalent bond.
📷 Congratulations, you have completed a molecule of hydrogen! Because the molecule has two atoms, it
is a diatomic molecule. Click the camera ( ) icon to take a snapshot of your completed molecule.
Right-click the image, and click Copy Image. Paste the image into the document below and label the image
“H2.”
📷
3. ✏️ Draw a diagram: Covalent bonds are shown in Lewis diagrams. In a Lewis diagram, dots represent
unshared valence electrons and dashes represent pairs of shared electrons.
Reproduction for educational use only. Public sharing or posting prohibited. © 2020 ExploreLearning™ All rights reserved