Properties of Liquids and their Interactions
Explore the properties of liquids and solids and how they interact.
What You Need
- Conical tube with approx. 5 ml of corn syrup (1 per student)
- Conical tube with approx. 5 ml of vegetable oil (1 per student)
- 1/2 ounce plastic or paper cup (1 per student)
- 1/2 tsp. of sugar in baggie (1 per student)
- Heaping tsp. of baking powder (1 per student) and 2-3 tsp. of baking powder in a baggie
- 8 or 10 oz clear cup (1 per student)
- Small waxed paper or plastic plate (1 per student)
- Stir stick (1 per student)
- Paper napkins
- Safety goggles
- Film cannister with a tight fitting lid
- Plastic spoon
- Large paper plate
- 2 or 3 tablecloths
Guide:
See attached guide for alternative activity supply list for virtual learners.
Safety Notes
Ensure you are familiar with Let's Talk Science's precautions with respect to safe virtual outreach to youth.
Students should not takes or eat any of the materials used in today's workshop.
What To Do
Introduction
- Explain the term 'properties' by using examples of properties of humans.
- Discuss different types of liquids and what makes each a liquid. It's okay if students do not know - that is what we will be exploring next!
Activity: Exploring Liquids
- To begin, students will explore the physical properties of liquids. Ask "do all liquids look and feel the same?"
- Give each student a small plate, a tube of corn syrup, a tube of oil and a small cup of water.
- Allow students to explore each liquid for 5-7 minutes. They can do so by:
- looking at the liquids
- touching the liquids with their fingers
- smelling the liquids
- listening to the liquids while swirling the tube around
- Note: remind the group to not cannot eat/taste the liquids!
- Afterwards, have students share their observations.
- Demonstrate how liquids take on the shape of a container by pouring water from a plastic baggie into a clear cup.
- They likely would have mixed liquids during the exploration. Ask them to share their observations. What happens when we mix liquids?
- Demonstrate what happens when we mix certain liquids by pouring a bit of corn syrup, water and oil into a clear plastic cup. Make sure that everyone has the chance to view the layers.
- Discuss why oil and water do not mix.
Activity: Exploring Solids
- Distribute large plastic cups with water, a stir stick and baggies of sugar and baking powder to each student.
- Start with the stir stick (a solid). Ask "can you pour the stir stick like the other liquids?"
- Discuss the differences between solids and liquids.
Activity: Liquid-Solid Interactions
- Explain that sugar is a very small solid, and have students try to see a single piece of sugar.
- Instruct students to add their sugar to the cup of water and stir.
- Discuss what happens (it dissolves).
- Have students add baking powder to the sugar water - bubbles should form.
Wrap-up
- Review what just happened- we mixed solids with liquids and had two different reactions! One mixture resulted in the solid dissolving into the liquid, while the other formed something new - a gas with many bubbles.
- Discuss what might happen if we mixed the baking powder in water in a container with a tight lid.
- Fill the film cannister 1/2 way with water.
- Place a paper plate on the floor away from students and pointing away from the ceiling lights.
- Put on safety goggles.
- Add about 1/2 tsp of baking powder to the film cannister, tightly secure the lid and place it (lid side up) on the paper plate. What happens?
- Explain that the container is being filled with gas bubbles and that the gas is strong enough to make the lid pop off.
- Discuss careers related to the topics discussed in today's workshop and what students will need (education, experience, etc.) to get into those careers.
Discovery
Matter is everything around us. Matter is made up of building blocks that are called molecules. There are three states of matter - solid, liquid and gas. The molecules in solids keep their shape because they are very close together and do not move around much. Molecules in liquids are further apart and can move around, but close enough that they keep the shape of the container they are in. The molecules in gases are the furthest apart and take up all the remaining space around us. Gases do not have a definite shape, but they will expand to take up all available space, so that all the molecules are very far apart from one another.
When a solid dissolves in a liquid, you can no longer see the solid but it is still there. Some liquids, such as oil and water, will not mix regardless of how much they are stirred or shaken. This is because water molecules like to stick so close together that the oil molecules are unable to get in between them.
A reaction occurs when baking powder (solid) mixes with water (liquid). This reaction produces carbon dioxide (gas). In this demonstration, the lid of the film cannister traps the carbon dioxide gas molecules. Because gas molecules want to fill up as much room as possible, they push against the sides of the cannister and eventually makes the lid pop off.
Chemistry is the study of matter and how molecules interact. Chemistry helps us understand the world around us and our own bodies. We use chemistry to do many things, from baking a cake to making medicine to take when we are sick. It is important to understand how matter will behave since it is always interacting!
What's Happening?
Matter is everything around us. Matter is made up of building blocks that are called molecules. There are three states of matter - solid, liquid and gas. The molecules in solids keep their shape because they are very close together and do not move around much. Molecules in liquids are further apart and can move around, but close enough that they keep the shape of the container they are in. The molecules in gases are the furthest apart and take up all the remaining space around us. Gases do not have a definite shape, but they will expand to take up all available space, so that all the molecules are very far apart from one another.
When a solid dissolves in a liquid, you can no longer see the solid but it is still there. Some liquids, such as oil and water, will not mix regardless of how much they are stirred or shaken. This is because water molecules like to stick so close together that the oil molecules are unable to get in between them.
A reaction occurs when baking powder (solid) mixes with water (liquid). This reaction produces carbon dioxide (gas). In this demonstration, the lid of the film cannister traps the carbon dioxide gas molecules. Because gas molecules want to fill up as much room as possible, they push against the sides of the cannister and eventually makes the lid pop off.
Why Does It Matter?
Chemistry is the study of matter and how molecules interact. Chemistry helps us understand the world around us and our own bodies. We use chemistry to do many things, from baking a cake to making medicine to take when we are sick. It is important to understand how matter will behave since it is always interacting!