Name: ______________________________________ Date: ________________________
Student Exploration: Melting Points
Vocabulary: boiling point, covalent bond, intermolecular forces, ionic bond, melting point,
metallic bond, molecular solid, network solid, salt, smoke, sublimation, sublimation point,
transition point
Prior Knowledge Questions (Do these BEFORE using the Gizmo.)
1. Suppose you had two socks sticking together in the clothes dryer from static electricity.
What happens if they are spun gently?
2. What could happen if they are tumbled rapidly?
Gizmo Warm-up
Like socks in the dryer, solids are held together by molecular-
scale forces. When solids are heated, molecules move faster
and spread apart as the solid becomes liquid and gas. In the
Melting Points Gizmo, you will measure the transition points at
which melting and boiling occur for a variety of substances.
The Gizmo shows a lab device used to determine melting points and boiling points. A small
amount of substance is placed in a glass tube and heated inside the device.
1. To begin, check that Sodium chloride is selected. Drag the dial to the right to apply heat.
A. When the temperature is around 600 °C, drag the dial back to 0. Notice that the
sodium chloride is red-hot, but it is still a solid.
B. Drag the dial to the right. When the sodium chloride melts, move the dial back to 0.
About what temperature does sodium chloride melt?
