Properties of Water Lab Data Sheet

Names ______Date____/____/____ Hour _____

Properties of Water

Water is the most important molecule to life. It has many properties which make it a very unique substance. It is very small, it is attracted to itself as well as other surfaces, it causes surface tension on water, and will travel up capillaries against the force of gravity. This lab consists of a series of “mini-labs” which demonstrate some of these properties of water.

In all mini-labs, you are to first make a prediction, then conduct the steps of the lab, record your results or observations, then answer the analysis questions. This lab demonstrates adhesion, cohesion, capillary action, and surface tension.

Lab 1: Paper Chromatography of Black Ink

Problem: What will happen to the black ink?

Hypothesis: I think the ink will….

Observations: What did you see!!

Analysis Questions

  1. Which colors of the black ink are made of the heaviest molecules?
  1. Which colors of the black ink are made of the lightest molecules?
  1. What was the force that allowed the water to travel against gravity?
  1. How does the size of the molecules affect their ability to travel?

Lab 2: Drops on the Penny

Problem: How many drops of water can you get on the penny without spilling?

Hypothesis: I think I can get ______drops of water on top of a penny before it spills over.

Observations: How many did you fit? ______

Analysis Questions

  1. Explain what properties of water (2) allowed you to get so many drops to stay on the penny?
  1. What is the role of hydrogen bonding in this activity?
  1. Where is cohesion demonstrated? Where is adhesion demonstrated?

Lab 3: Sand Castle

Problem: How does dry sand behave compared to wet sand?

Hypothesis: I think the ______sand will build a better sand castle.

Observations: What did the wet sand do? ______

What did the dry sand do? ______

Analysis Questions

  1. Explain what properties of water make a difference between sculpting dry sand and wet sand?
  1. What is the role of hydrogen bonding in this activity?

Lab 4: Water and the Glass Slides

Problem: What will happen to two glass slides if you put a drop of water in between them and try to pick up the top slide?

Hypothesis: I think the slides will ______.

Observations: What did you see? ______

Analysis Questions

  1. What properties of water allowed you to observe what you saw?
  1. What is the role of hydrogen bonding in this activity?

Lab 5: Does 10 + 10 = 20?

Problem: What will be the total measured volume if I mix 10-ml of rubbing alcohol with 10-ml of water? (It is not 20 ml!!!)

Hypothesis: I think the volume will be ______ml.

Observations:

Analysis Questions

  1. What property allowed you to observe the results that you witnessed? (Hint: Water is a very small molecule and alcohol is a very large molecule)

Lab 6: Walking on Water

Problem: How can I make a paper clip stay on top of water? It can be done.

Hypothesis: I think if I ______the paper clip, it will stay on top of the water.

Observations: Could you get it to stay on top? ______Could others? ______

Analysis Questions

1. What property of water allowed youmake the paperclip stay on top of the water?

  1. Explain how “water skipper bugs” are able to live their life on top of water.

3. Was the paper clip floating? Why or why not?