Coluna Arco-Íris de Densidades

Empilhamento de líquidos de diferentes densidades para criar uma coluna colorida

Classroom Demonstrations Beginner (Middle School) 30 min ~$8,00

Objetivo

Demonstrar o conceito de densidade de líquidos empilhando líquidos imiscíveis de diferentes densidades em uma coluna alta.

Contexto

Different liquids have different densities, and immiscible liquids will arrange themselves with the densest at the bottom and the least dense at the top. By carefully layering liquids such as honey, corn syrup, dish soap, water, vegetable oil, and rubbing alcohol, a dramatic rainbow column can be created. Small solid objects placed in the column float at the interface matching their density, further illustrating the concept.

Avisos de segurança

  • Rubbing alcohol is flammable — no open flames
  • Some liquids are sticky — clean spills immediately
  • Do not drink any of the layered liquids

EPI necessário

goggles

Materiais

  • Honey (50 mL)
    Density ≈ 1.42 g/mL
  • Corn syrup (50 mL)
    Density ≈ 1.38 g/mL
  • Maple syrup (50 mL)
    Density ≈ 1.32 g/mL
  • Dish soap (50 mL)
    Density ≈ 1.06 g/mL
  • Water (dyed blue) (50 mL)
    Density = 1.00 g/mL
  • Vegetable oil (50 mL)
    Density ≈ 0.92 g/mL
  • Rubbing alcohol (dyed red) (50 mL)
    Density ≈ 0.79 g/mL
  • Food coloring (Various)
    To distinguish water and alcohol layers

Equipamentos

Tall clear glass or graduated cylinder (500 mL) Funnel or turkey baster Small objects: grape, cherry tomato, ping pong ball, bolt, cork

Procedimento

1

Start with the densest liquid: pour honey slowly into the bottom of the tall glass.

2 min
2

Tilt the glass slightly and pour corn syrup slowly down the side. It should form a distinct layer on top of the honey.

3 min
3

Continue adding layers in order of decreasing density: maple syrup, dish soap, blue-dyed water, vegetable oil, and red-dyed rubbing alcohol.

15 min Pour very slowly for clean layers
4

Observe the distinct layers. Gently drop small objects (grape, bolt, cork, ping pong ball) into the column and note where they settle.

5 min
5

Discuss why the layers form (density differences), why some are miscible and some immiscible, and why objects float at specific levels.

5 min

Resultados esperados

Seven distinct layers should be visible, creating a colorful rainbow column. A metal bolt sinks to the bottom, a grape rests on the corn syrup, a cherry tomato on the dish soap, and a ping pong ball floats on top. Cork floats on the water layer.

Limpeza

Pour the column into a waste container (do not pour down the drain due to oil and syrup). Wash the glass with hot soapy water.

Detalhes

Categoria
Classroom Demonstrations
Dificuldade
Beginner (Middle School)
Duração
30 min
Custo estimado
$8,00
Passos
5
Materiais
8

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Frequently Asked Questions

What is the objective of Coluna Arco-Íris de Densidades?
Demonstrar o conceito de densidade de líquidos empilhando líquidos imiscíveis de diferentes densidades em uma coluna alta.
How difficult is Coluna Arco-Íris de Densidades?
This experiment is rated as Beginner (Middle School). It takes approximately 30 minutes to complete.
What safety precautions are needed for Coluna Arco-Íris de Densidades?
Key safety precautions include: Rubbing alcohol is flammable — no open flames; Some liquids are sticky — clean spills immediately; Do not drink any of the layered liquids.
What materials are needed for Coluna Arco-Íris de Densidades?
The main materials required are: Honey, Corn syrup, Maple syrup, Dish soap, Water (dyed blue).
What results should I expect from Coluna Arco-Íris de Densidades?
Seven distinct layers should be visible, creating a colorful rainbow column. A metal bolt sinks to the bottom, a grape rests on the corn syrup, a cherry tomato on the dish soap, and a ping pong ball floats on top. Cork floats on the water layer.