Water Property Vocabularies:
- Polarity: This property has the ability to dissolve or dissociate most compounds. Allowing water to break or dissociate apart ion.
- Cohesion: Water is able yo pull itself into a small shape (sphere). Water molecules are attracted to the other water molecule.
- Surface Tension: Water molecules attracted to themselves by the attraction of the particles.
- Adhesion: Water attracted to a material/substance.
- Effect of Heat on Water: High heat of vaporization = hydrogen bonds must be broken so water can absorb a lot of heat without changing phase.Evaporates slowly for cooling effect.
- High Latent Heat of Fusion = a lot of heat is released when water freezes and a lot of heat is absorbed when ice melts.
- High Specific Heat: This means that water can absorb large amount of heat before it begins to get hot. It helps water regulate the rate at which air changes temperature.
Station 1: Evaporative Cooling - Water & Alcohol
In this experiment you place one drop of water and alcohol next to each other on the back side of your hand (you can blow on your had to tell which is cooler). After doing that which feels cooler?
Answer - The alcohol feels cooler.
In order to get rid of excess heat you sweat. The sweat absorbs heat and evaporates away - taking with it heat energy.
Why is it beneficial that your sweat is water and not alcohol?
Answer - It is beneficial to sweat water instead of alcohol instead because the alcohol evaporates faster. Since alcohol evaporates too fast, it won't be able to absorb much heat which means you won't be able to cool down.
In this experiment you place one drop of water and alcohol next to each other on the back side of your hand (you can blow on your had to tell which is cooler). After doing that which feels cooler?
Answer - The alcohol feels cooler.
In order to get rid of excess heat you sweat. The sweat absorbs heat and evaporates away - taking with it heat energy.
Why is it beneficial that your sweat is water and not alcohol?
Answer - It is beneficial to sweat water instead of alcohol instead because the alcohol evaporates faster. Since alcohol evaporates too fast, it won't be able to absorb much heat which means you won't be able to cool down.
Station 2: Water Tension/Cohesion - Water on a Penny
In this experiment you predict how many drops of water will fit on a penny before it overflows. You use a pipette to add drops on the penny until it overflows. As you count the drops of water, make sure you observe carefully.
I predicted 5 drops.
How many drops fit on the penny before overflow and how was it able to hold that many drops?
Answer - 24 drops of water fitted on the penny before overflowing. Cohesion and adhesion helped support the water to stay on the penny.
In this experiment you predict how many drops of water will fit on a penny before it overflows. You use a pipette to add drops on the penny until it overflows. As you count the drops of water, make sure you observe carefully.
I predicted 5 drops.
How many drops fit on the penny before overflow and how was it able to hold that many drops?
Answer - 24 drops of water fitted on the penny before overflowing. Cohesion and adhesion helped support the water to stay on the penny.
Station 3: Surface Tension - Water on Wax Paper
In this experiment you place a drop of water on to the wax paper and write down observations.
Observations: The wax paper absorbs the water slowly. The wax paper absorbs water faster than the paper.
In this experiment you place a drop of water on to the wax paper and write down observations.
Observations: The wax paper absorbs the water slowly. The wax paper absorbs water faster than the paper.
Station 4: Surface Tension - Paper Clips on the Surface of a Cup of Water
In this this experiment, you fill a cup with water. You use tweezers to carefully float a paperclip on the surface of the water.
How many can float before sinking?
I predicted - 5.
Carefully add one drop of dish soap to the water and explain what happens now.
Answer - The dish soap breaks the water down and makes the paper clip sink.(breaks the bonds)
In this this experiment, you fill a cup with water. You use tweezers to carefully float a paperclip on the surface of the water.
How many can float before sinking?
I predicted - 5.
Carefully add one drop of dish soap to the water and explain what happens now.
Answer - The dish soap breaks the water down and makes the paper clip sink.(breaks the bonds)
Station 5: Adhesion - Graduate Cylinder
Put some water in the a graduate cylinder. Look at the "meniscus." Explain why the water is not straight across the glass container.
Answer - It is not straight because of Adhesion.
Why would adhesion be an important property to living systems?
Answer - Adhesion can stick water to a plant's root so it can suck it in for chemical reactions as photosynthesis.
Put some water in the a graduate cylinder. Look at the "meniscus." Explain why the water is not straight across the glass container.
Answer - It is not straight because of Adhesion.
Why would adhesion be an important property to living systems?
Answer - Adhesion can stick water to a plant's root so it can suck it in for chemical reactions as photosynthesis.
Station 6: Capillary Action - Rolled up Paper Towel
On this experiment roll up a piece of paper towel and get a cup full of water(dye it blue). Also get another cup empty though. Then you place one end of the paper towel in the cup full of water and one end in the empty cup. Observe and explain why would capillary action be important to plants and trees?
Answer - Capillary action absorbs water for plants and trees so they can use it to survive.
On this experiment roll up a piece of paper towel and get a cup full of water(dye it blue). Also get another cup empty though. Then you place one end of the paper towel in the cup full of water and one end in the empty cup. Observe and explain why would capillary action be important to plants and trees?
Answer - Capillary action absorbs water for plants and trees so they can use it to survive.