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Exploding Pumpkin (6 Favorites)

LAB in Classification of Reactions. Last updated May 30, 2017.


Summary

In this lab, students use a chemical reaction to create an explosion inside of a pumpkin.

Grade Level

High school

Objectives

By the end of this lesson, students should be able to

  • explain changes in energy during chemical reactions.

Chemistry Topics

This lesson supports students’ understanding of

  • Chemical reactions

Time

Teacher Preparation: 2 class periods (100 minutes)

Lesson: 1 class period (50 minutes)

Materials

For each group:

  • Pumpkin
  • Knives
  • Calcium carbide
  • Water
  • Fire source
  • Dixie cup
  • Wood splint

Safety

  • Always wear safety goggles when working with chemicals in a laboratory setting.
  • Use caution when working with fire or around explosives.

Teacher Notes

  • This lab should be performed outside.
  • Depending on your comfort level, you may want to light the pumpkins for the students.
  • When it comes time to light the pumpkin, make sure students are at a safe distance away from the pumpkin(s).

For the Student

Lesson

Introduction
Many people celebrarte Halloween by carving pumpkins. Today, you are going to do just that, with a catch. Instead of just a simple carve, you will create an explosion inside the pumpkin that will carve it for you!

Materials

  • Pumpkin
  • Knives
  • Calcium carbide
  • Water
  • Fire source
  • Dixie cup
  • Wood splint

Procedure

Preparation (inside)

  1. Cut a circle around the stem of the pumpkin so you can remove it. This is the lid of your pumpkin. If the inside is really thick, slice away the excess until you have about one half of an inch of inside remaining. Set the lid aside.
  2. Clean out the inside of the pumpkin and discard the seeds.
  3. Cut out the design that you want carved in the pumpkin. If the insides of these cut pieces are too thick, slice away the excess until you have about one half of an inch of inside remaining.
  4. Cut out a square on the back of the pumpkin near the bottom and throw it away. This is where you will light the pumpkin.
  5. Replace all other pieces.

    Explosion (outside)

  6. Put one scoop of calcium carbide into a Dixie cup. Set the Dixie cup upright in the bottom of the pumpkin.
  7. Pour 20 mL of water into the Dixie cup and immediately replace lid.
  8. Within 30-45 seconds, light the wood splint on the end of your apparatus and bring the lit splint to the square on the back of the pumpkin and light the inside.

Analysis

  1. Explain in your own words what happened inside the pumpkin.