how does salt affect the freezing point of water experiment

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Salt and the freezing point of water

Introduction: (initial observation).

In winter time we spread salt in the roads and side walks to melt snow and ice or to prevent ice. How does salt melt ice or snow? Do other material do the same? Is salt creating heat to melt the snow? Is it changing the freezing point of water so water does not freeze at 0ºC (32º F)?

In this project we will perform an experiment to see if the salt has any affect on the freezing point of water.

This project guide contains information that you need in order to start your project. If you have any questions or need more support about this project, click on the “ Ask Question ” button on the top of this page to send me a message.

If you are new in doing science project, click on “ How to Start ” in the main page. There you will find helpful links that describe different types of science projects, scientific method, variables, hypothesis, graph, abstract and all other general basics that you need to know.  

Project advisor

Information Gathering:

Find out about freezing and freezing point. Read books, magazines or ask professionals who might know in order to learn about the effect of salt on the freezing point of water. Keep track of where you got your information from. freezing point: the   temperature at which the solid and liquid  phases of a substance are in equilibrium.

http://hyperphysics.phy-astr.gsu.edu/hbase/chemical/meltpt.html

Changes in the physical properties of solutions caused by solutes is known as the colligative properties of solutions. Change in freezing point is one of the colligative properties. Wikipedia, the free online encyclopedia has a good description for how solutes affect the properties of solutions. See the following link for more details:

http://en.wikipedia.org/wiki/Colligative_properties

Question/ Purpose:

What do you want to find out? Write a statement that describes what you want to do. Use your observations and questions to write the statement.

The purpose of this project is to determine the effect of salt on the freezing point of water.

Identify Variables:

When you think you know what variables may be involved, think about ways to change one at a time. If you change more than one at a time, you will not know what variable is causing your observation. Sometimes variables are linked and work together to cause something. At first, try to choose variables that you think act independently of each other.

This is how you may define the variables:

• The independent variable (also known as manipulated variable) is the amount of salt in water. The amount of salt in water may be reported as the percent of salt in water or as grams of salt per liter of water.
• The dependent variable (also known as responding variable) is the freezing point of water. Freezing point is the temperature in which water will freeze.
• Constants are the amount of water in each cup.
• Controlled variable is not needed because your experiment trials are performed at the same time or under the same environmental conditions.

Hypothesis:

Based on your gathered information, make an educated guess about the effect of salt on freezing point of water.

This is a sample hypothesis:

Since salt is used to de-ice roads in the winter, then it probably reduces the freezing point because it keeps ice from forming.

Experiment Design:

Design an experiment to test each hypothesis. Make a step-by-step list of what you will do to answer each question. This list is called an experimental procedure. For an experiment to give answers you can trust, it must have a “control.” A control is an additional experimental trial or run. It is a separate experiment, done exactly like the others. The only difference is that no experimental variables are changed. A control is a neutral “reference point” for comparison that allows you to see what changing a variable does by comparing it to not changing anything. Dependable controls are sometimes very hard to develop. They can be the hardest part of a project. Without a control you cannot be sure that changing the variable causes your observations. A series of experiments that includes a control is called a “controlled experiment.”

Experiment 1: Test the effect of table salt (sodium chloride) on the freezing point of water.

Introduction : In this experiment we will make different solutions of table salt with different concentrations and test to see at what temperature they freeze.

Procedure :

• Fill up 5 cups with 100 ml of water each. For the best results, you may use distilled water for this experiment. distilled water can be purchased from pharmacies. If you don’t have access to distilled water, use regular drinking water instead.
• Number the cups from 1 to 5 and label them.
• Do not add any salt to cup number 1. That will be your control.
• Add 5 grams of salt to the cup number 2 and stir it.
• Add 10 grams of salt to the cup number 3 and stir it.
• Add 15 grams of salt to the cup number 4 and stir it.
• Add 20 grams of salt to the cup number 5 and stir it.
• Place one thermometer in each cup.
• Place all the cups in the freezer and set your freezer to the coolest possible temperature.
• Inspect the condition of each cup (Frozen or not) and record the temperature every 10 minutes. The temperature you record for each cup is the temperature in which the water is partially frozen.
• Record the results in a table like this:
• L – 12ºC is an example of recorded data and means the sample is still Liquid and it’s temperature is 12 degrees centigrade.
• F – 0ºC means the sample is partially or fully Frozen and the temperature is zero degree centigrade.
• If you don’t have 5 thermometers, use one to check the temperature of each cup. To avoid transferring salt from one cup to the other, you will need to clean the thermometer with water and paper towel after measuring the temperature of each cup.
• For these experiments you will need a thermometer that can show as low as -20ºC or 0ºF.
• C = Celsius Temperature Scale (Centigrade)
• F = Fahrenheit
• If you don’t have a scale to weight 5 grams s

Materials and Equipment:

• Thermometer* (available at science suppliers),
• plastic or aluminum cup,

* Glass and dial thermometers shown above are available at   MiniScience.com and klk.com . Either of the two models may be used for freezing temperatures. Dial thermometers last longer; however, glass thermometers are more accurate.

Results of Experiment (Observation):

The above table will be completed and used as the result of your experiment. You may also write in a paragraph or two the result. What you write may be an answer to the following questions:

1. What was the lowest temperature that the salt water reached?

2. Did the salt water solidify completely?

3. Is the freezing point for salt water below, the same as, or above the freezing point for pure water?

4. At what temperature does the pure water solidify?

5. Lake Winnipeg is a freshwater lake. If there was a salt lake located right beside Lake Winnipeg and it was the same size which lake would freeze first? Why?

6. Why is salt sprinkled on our streets in the winter?

You may also us the result of your experiments to make a bar chart. Each bar represents certain amount of salt and the height of that will represent the freezing point. Following is a bar chart made with non-real data. you will need to make your own, using the result of your own experiment.

Calculations:

No calculation is required

Summary of Results:

Summarize what happened. This can be in the form of a table of processed numerical data, or graphs. It could also be a written statement of what occurred during experiments.

It is from calculations using recorded data that tables and graphs are made. Studying tables and graphs, we can see trends that tell us how different variables cause our observations. Based on these trends, we can draw conclusions about the system under study. These conclusions help us confirm or deny our original hypothesis. Often, mathematical equations can be made from graphs. These equations allow us to predict how a change will affect the system without the need to do additional experiments. Advanced levels of experimental science rely heavily on graphical and mathematical analysis of data. At this level, science becomes even more interesting and powerful.

Conclusion:

Using the trends in your experimental data and your experimental observations, try to describe the effect of salt on freezing point of water. Is your hypothesis correct? Now is the time to pull together what happened, and assess the experiments you did.

Related Questions & Answers:

What you have learned may allow you to answer other questions. Many questions are related. Several new questions may have occurred to you while doing experiments. You may now be able to understand or verify things that you discovered when gathering information for the project. Questions lead to more questions, which lead to additional hypothesis that need to be tested.

You may repeat such experiment on other types of salts such as Epsom salt (Magnesium sulfate) and Salt cake (Sodium sulfate).

Possible Errors:

If you did not observe anything different than what happened with your control, the variable you changed may not affect the system you are investigating. If you did not observe a consistent, reproducible trend in your series of experimental runs there may be experimental errors affecting your results. The first thing to check is how you are making your measurements. Is the measurement method questionable or unreliable? Maybe you are reading a scale incorrectly, or maybe the measuring instrument is working erratically.

If you determine that experimental errors are influencing your results, carefully rethink the design of your experiments. Review each step of the procedure to find sources of potential errors. If possible, have a scientist review the procedure with you. Sometimes the designer of an experiment can miss the obvious.

References:

List of References:

Salt and Freezing Point of water

Freezing point depression

Use of salt in Making ice cream

Science in ice cream

Sample Display:

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Science Project

Water Freezing Point - Including Saltwater Tests

Posted by Admin / in Matter Experiments

It is well-known that the freezing temperature of water is 0°C or 32°F. Is there any way to change the freezing temperature of water? By performing this simple 30 minute experiment you will find out. Freezing temperature of water is tested by mixing water with some different materials and then performing freezing tests.

Materials Needed

• Clean tap water
• Cold Outside Temperature or a Freezer
• Thermometer (liquid) - Optional
• Thermometer - (atmosphere) or smart phone

EXPERIMENT STEPS

Step 1: Fill 3 small containers with water. Each container must have about the same amount of water. Do not fill the containers too full because they will need to be moved. Place a thermometer in one of the water containers and take a reading of the plain water termperature. The three liquid containers will all have the same starting temperature.

Step 2: Make a table salt (sodium Chloride) and water solution. The maximum amount of salt that typical tap water can hold until saturation is about one part salt and three parts water. We will not use this much because it takes too long to stir in the salt to get it to completely solution. Instead, we are using small containers so we only used about 2 teaspoons. Mix in all of the salt until there are no more crystals at the bottom. It will take a few minutes.

Mix a solution of table salt and water

Step 3: Next make an epsom salt (magnesium sulfate) and water solution. Epsom salt is much easier to mix with water. Again, we only used a few teaspoons full of epsom salt with our small containers.

Mix a solution of epsom salt (magnesium sulfate) and water

Step 4: Place all three containers outside or in a freezer. The outside temperature must be lower than freezing for this experiment to work. Start a stopwatch timer to begin tracking the amount of time it takes for the water samples to freeze.

Set the timer to see how long it takes for each of the water solutions to freeze

Step 5: Measure and record the starting temperature of the air outside or in the freezer.

Measure the air temperature (or freezer temperature)

Step 6: Observe the mixtures and record the time when each of the water samples freeze. This is the time when the top of the sample freezes. It will take much longer for the entire sample to freeze. We will understand the results by only observing a freezing of the surface.

Observe the solutions and record how long it takes for the water, epsom saltwater and table saltwater to freeze

Step 7: Take a measurement of the air temperature at the end of the experiment to make sure it has not changed much.

SCIENCE LEARNED

What results were observed during your experiment? You probably saw that pure water froze first, followed closely by the epsom salt solution. Saltwater takes a little longer thant the other samples to freeze, but if it is cold enough, saltwater will freeze. In general, water freezes at 0°C (32°F) and ocean saltwater freezes at 28.4°F (-1.9°C), but there are some additional factors that effect the temperature and how long each of the samples take to freeze. Here are some factors that will change either the temperature or the amount of time the samples take to freeze (or both):

• Starting Temperature of the Samples
• The air temperature
• Atmosphere - Elevation and Atmospheric Pressure
• Amount of salt or epsom salt in each solution
• Contaminants in the water
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How does salt affect the freezing point of water.

Welcome to our informative article about how salt affects the freezing point of water! If you’re here, you are probably either curious about how something you use almost every day impacts water, or you’re a student or professional studying the chemical or physical properties of water. Whatever your reason for coming here, we are here to help you better understand how salt affects the freezing point of water.

Introduction

Water is one of the essential substances for life. It’s a clear, tasteless liquid that maintains life and habitat for plants and animals. As it freezes, it expands, creating ice, a vital part of our wintertime activities. However, salt can change the normal freezing process of water by lowering its freezing point.

In this article, we will discuss how salt affects the freezing point of water and its advantages and disadvantages. We will also provide a table detailing the complete information you need to know regarding this topic, followed by frequently asked questions (FAQs) that will help you understand the concept better.

When you add salt to water, it lowers the freezing point of the water. Pure water freezes at 0°C (32°F), but saltwater freezes at a lower temperature. The salt particles disrupt the hydrogen bonding between the water molecules, making it harder for the water molecules to connect in an ordered way and form ice crystals, which slows down the freezing process.

As you add more salt to water, the freezing point drops. The more salt you add, the lower the freezing point becomes. The freezing-point depression depends on the concentration of the salt in the water.

The equation below shows how the freezing point of water changes when salt is added:

As you can see in the table above, the more concentrated the salt, the lower the freezing point of water.

Advantages and Disadvantages of Salt Affecting the Freezing Point of Water

There are many advantages to knowing how salt affects the freezing point of water. Here are a few of them:

1. Easier Winter Driving

In cold weather, salt is commonly used to prevent the roads from freezing. When salt is spread on the road, it lowers the freezing point of the water, preventing dangerous ice from forming. With salt treatment, drivers can have a safer driving experience in the winter months.

2. Ice Cream Making

Salt can be used in ice cream making. The freezing point depression caused by added salt to ice allows the temperature of the ice to be lower than freezing, which is necessary to freeze the ice cream mixture. The addition of salt to ice can also make the ice cream freeze faster, saving time and energy.

3. Science Experiments

In chemistry, it’s essential to understand how solvents and solutes interact. For instance, salt is commonly used in science experiments such as cryoscopy, which involves determining the molecular weight of substances dissolved in solvents such as water.

Disadvantages

There are also some disadvantages to salt affecting the freezing point of water. Below are a few of them:

1. Corrosion

When salt dissolves in water, it creates an electrolyte solution that can cause corrosion. The corrosion can cause damage to cars, buildings, and other infrastructure, requiring costly repairs.

2. Environmental Impact

Salt from roads and sidewalks can leach into groundwater or surface water, causing harm to vegetation, aquatic life, and other animals.

3. Health Concerns

The consumption of large amounts of salt can lead to high blood pressure and other health concerns.

Frequently Asked Questions (FAQs)

1. what happens when you add salt to ice.

When salt is added to ice, it lowers the freezing point of the ice, resulting in the formation of a brine solution that melts the ice faster, making it easier to clear away.

2. Can you separate salt from ice after adding it?

No, you cannot separate salt from ice once it’s added.

3. Why is salt used to melt ice?

Salt is used to melt ice because it lowers the freezing point of water, making it easier to melt.

4. Can salt affect the boiling point of water too?

Yes, salt can affect the boiling point of water. When salt is added to water, it raises the boiling point of the water.

5. Is it safe to eat snow with salt on it?

No, it’s not safe to eat snow with salt on it because the added salt can cause dehydration. Eating too much salt can lead to high blood pressure and other health concerns.

6. Can salt make water freeze faster?

No, salt can’t make water freeze faster.

7. How much salt should I add to the ice cream mixture?

It’s recommended to add 6 tablespoons of salt to 2 cups of ice when making ice cream.

8. Does the type of salt used matter?

Yes, the type of salt used can affect the freezing point of water. Table salt, sea salt, and rock salt all have different effects on the freezing point of water.

9. Can you use sand instead of salt on the roads?

Yes, sand is also commonly used on roads in colder climates. Sand doesn’t melt the ice, but it provides traction in slippery conditions.

10. Is saltwater denser than freshwater?

Yes, saltwater is denser than freshwater because salt adds to the weight of the water.

11. Can you use salt to prevent water from freezing in pipes?

Yes, salt can be used to prevent water from freezing in pipes. Adding salt to water lowers its freezing point, making it less likely to freeze.

12. Is salt effective in melting snow at low temperatures?

Salt is less effective in melting snow at low temperatures, such as -15°C (-5°F) or lower, because the temperature is too low for salt to work effectively.

13. Can salt affect aquatic life?

Yes, salt can harm aquatic life by increasing water salinity levels, causing stress to freshwater fish and plants.

In conclusion, salt is an essential ingredient in lowering the freezing point of water. It can make winter driving safer, help in ice cream making, and aid with science experiments. However, it also has disadvantages, such as environmental impact, health concerns, and corrosion.

Understanding how salt affects the freezing point of water is vital for anyone involved in chemistry, physics, or anyone curious about the physical properties of water. Hopefully, this article has provided you with useful information about how salt affects the freezing point of water.

This article is for informational purposes only and should not be used as a substitute for professional advice. Always consult a professional before making any decisions related to your health, safety, or finances.

Watch Video:How Does Salt Affect the Freezing Point of Water?

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How Does Salt Affect Ice? A Simple Science Experiment

Looking for a way to explain to your learners why salt is utilized to combat icy roadways and sidewalks? Check out this simple science experiment to demonstrate how salt affects the freezing point of water and how the over-utilization of salt can be harmful to the environment.

Every winter before a storm, large trucks rumble down the road through my neighborhood, spreading salt crystals over the pavement. My six-year-old was curious about why these trucks appeared before a storm and so I decided to not only tell him but to show him, with a simple science experiment.

The Simple Science of Water and Salt

To provide my kids with a bit of background information, I broke out my chemistry modeling set and gave them a brief description of what’s happening at the molecular level.

Water is a molecule that is made up of two elements: hydrogen and oxygen. Water, also written as H 2 O, freezes at 0℃ or 32℉. However, when a compound like sodium chloride, NaCl, what we commonly refer to as salt, is dissolved in water, something interesting happens. The salt compound breaks apart into sodium and chlorine ions and prevents the water molecules from bonding together at their normal freezing point of 0℃ or 32℉. The addition of salt actually lowers the freezing point of water! 

When this occurs, we can’t actually see the sodium and chlorine ions at work, as they are way too small for our eyes to observe. What we do notice is that, when salt is applied to ice, the ice begins to melt. This is because the composition of water is no longer plain H 2 O; it now has sodium and chlorine ions floating around in it, causing the freezing point to decrease.

How’s that for some snazzy science?

Making the Science of Salt and Water Visible

In order to visualize the concept of salt lowering the freezing point of water, I gathered a few simple supplies from my kitchen and got to work. This experiment took approximately 30 minutes for my kids to complete from start to finish, with additional time to discuss the environmental implications of adding salt to icy roadways.

Materials Needed for the Science Experiment

To demonstrate how salt affects the freezing point of water, you’ll need the following materials:

• 2 Ice cubes
• Table salt*
• Timer or Clock

*You can use either fine or coarse table salt for this experiment. I chose to use both to demonstrate the difference in melting time for each option. If you want to test both salt types as well, you will need 3 ice cubes and 3 bowls.

Make Predictions to Practice Critical Thinking Skills

To engage your learners in critical thinking (and to add an extra layer of fun to the science experiment!) have them make the following predictions prior to conducting the experiment:

• Which ice cube will melt the fastest?
• How much time will it take for the plain ice cube to melt?
• How much time will it take for the salty ice cube to melt?

Not only do these questions get students thinking about the experiment, but they also allow them to make mathematical comparisons to the results, engaging the “M” in STEM! Have your learners record their predictions in a table, like the one shown below. 

Title: What Effect Does Salt Have on Ice?

I’ll explain more about teaching students how to collect data in an organized manner in the data collection portion of this post.

Most importantly, this is a fun activity to get your kids thinking and making hypotheses. Most children are afraid of being “wrong”; this activity teaches them that being wrong is part of the fun! Taking educated guesses is what drives science forward because when we realize our answer is wrong, we can confidently move forward in the right direction! Try to foster the idea that it’s not the “right” or “wrong” answer that’s important, but rather the learning that happens as a result of the experiment.

Instructions to Conduct the Salty Ice Experiment

Follow these step-by-step instructions to visualize the effect salt has on the ice.

• Set the bowls on a level surface.
• Place an ice cube in each bowl.
• Label the first bowl as your control. This bowl will only contain an ice cube.
• Label the second bowl as your variable. 
• Into the second bowl, pour one teaspoon of table salt on top of the ice cube.
• Record the time or start a stopwatch
• Observe the difference in the time it takes for the two ice cubes to melt.

If you have chosen to test the effect that both fine and coarse table salt have on the ice cubes, add a step to the instructions, applying one teaspoon of the additional salt to a third ice cube.

The temperature of the surrounding air will affect the rate at which both ice cubes melt. You want to specifically focus on the difference in time between the melting rates of the ice cubes.

Simple Data Collection for the Science Experiment

This is a great activity to introduce or reinforce the importance of recording data in an organized manner. Create a simple table like the one below for your learners to write down their observations. Point out that a table must have a title, clear labels explaining what each value represents, along with the units of measurement used.

Here is an example of a table to use for the salty ice experiment:

If you have chosen to test an additional type of table salt, be sure to add an extra column to the table.

Discussion Questions for the Salty Ice Experiment

Once your learners have completed the salty ice science experiment, have them revisit their predictions and compare them to the results. Try to avoid statements such as, “Were your predictions right or wrong?” as the aim is not for them to be accurate in their assumptions, but instead to learn how to properly conduct an experiment and analyze results. Here are some prompts you can try to get them thinking:

• Which ice cube changed from solid to liquid first? Why do you think that happened?
• How does the melting time of the plain ice cube compare to your prediction? Did it melt faster or slower than you predicted?
• How does the melting time of the salted ice cube compare to your prediction? Did it melt faster or slower than you predicted?
• How can this knowledge be useful to someone that lives in a climate zone that receives ice and snow in the winter?

Depending on the age and ability level of your learners, have them calculate the numerical difference in predicted versus actual melting times of each ice cube to add an extra mathematical component to this lesson.

Environmental Implications of Using Salt to Decrease Ice Accumulation on Outdoor Surfaces

To apply what they have learned, introduce and discuss the environmental issues that arise when salt is applied in abundance to icy roadways and outdoor surfaces. You can utilize the video lesson I created with Medinah Eatman of Science Teacher Mom to guide this portion of their learning, beginning at the Nature Connection section, found at minute 15 of the virtual lesson. You’ll notice that I reference a printable in the video, which you can access for free here:

Here are the main takeaways from this section of the lesson:

• Excess salt washes into local waterways, causing problems for the plants and animals that reside there.
• Fresh water fish that reside in local waterways have hatchlings that are 30% smaller than average when exposed to higher salinity. Salinity is a value that addresses the amount of salt dissolved in water. 
• Increased salinity in freshwater can kill zooplankton and phytoplankton, which are important food resources for fish, clams, snails, and insects.
• Plants can be negatively affected by increased salinity, causing them to have smaller leaves, flowers, and fruit, as well as slower stem growth.
• Large mammals like deer and moose are attracted to the salted roadways, causing in increase in collision rate with these animals during winter months.

The lesson then goes on to discuss the appropriate level of salt to use per area of ice, as well as some salt alternatives currently available to treat icy surface conditions.

Making Science Easily Accessible

Conducting simple scientific experiments like this one allows students to see that science is everywhere and doesn’t require fancy equipment to conduct investigations. Additionally, their confidence in making predictions and interpreting information will grow, strengthening their critical thinking skills.

If you try this salted ice experiment, please let me know by tagging me @thoughtfullysustainable on Instagram or Facebook , or by leaving a comment below! If you have any questions, feel free to email me!  

Instructions

1. Set the bowls on a level surface. 2. Place an ice cube in each bowl. 3. Label the first bowl as your control. This bowl will only contain an ice cube. 4. Label the second bowl as your variable. 5. Into the second bowl, pour one teaspoon of table salt on top of the ice cube. 6. Record the time or start a stopwatch 7. Observe the difference in the time it takes for the two ice cubes to melt.

You can use either fine or coarse table salt for this experiment. I chose to use both to demonstrate the difference in melting time for each option. If you want to test both salt types as well, you will need 3 ice cubes and 3 bowls.

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Freezing Water Experiment

Explore the freezing point of water and discover what happens when you freeze saltwater. All you need are some bowls of water and salt. We love easy science experiments for kids !

Suggestion : Follow up this experiment with our ice melting experiment and investigate how salt affects the melting point of ice!

Recommended Grade Level: 3-5 (learn about applying the scientific method below)

Freezing Saltwater Instructions:

STEP 1: Label the bowls “Bowl 1” and “Bowl 2”.

STEP 2: Measure out 4 cups of water for each bowl.

STEP 3: Add 2 tablespoons of salt to bowl 2, a little at a time, stirring as you go.

STEP 4: Place both bowls in the freezer, check the bowls after a hour to see how they have changed.

Optional – use a thermometer to measure the water in both bowls.

STEP 5: Recheck them after 24 hours. What do you notice?

What is the Freezing Point of Water?

The freezing point of water is 0° Celsius / 32° Fahrenheit. But what temperature does salt water freeze at? If there is salt in the water, the freezing point is lower. The more salt in the water, the lower the freezing point and the longer the water will take to freeze.

What happens when water freezes? When fresh water freezes, water molecules of hydrogen and oxygen bind together, forming ice. Salt in the water makes it harder for the molecules to bind with the ice structure; the salt gets in the way of the molecules, blocking them from joining the ice. This is an example of a physical change !

That’s why saltwater takes longer to freeze. Salt is also sometimes used on icy roads to slow down freezing and make them safer to drive on.

Also check out our states of matter experiments !

Using the Scientific Method

The scientific method is a process or method of research. A problem is identified, information about the problem is gathered, a hypothesis or question is formulated from the information, and the hypothesis is tested with an experiment to prove or disprove its validity. Let’s do an example for freezing saltwater:

Ask a Question : What happens to water and saltwater when you freeze them? Will they freeze at the same time?

Make a Hypothesis : If salt is added to water, then the saltwater will take longer to freeze than plain water because the salt lowers the water’s freezing point.

Conduct an Experiment : Clearly outline your variables:

• Independent Variable : The type of water (plain vs. saltwater).
• Dependent Variable : The amount of freezing observed in the bowls over time.
• Control Variables : Amount of water, temperature in the freezer, same bowl type.

Click here to learn more about the scientific method and how to use it .

Free printable freezing saltwater science project!

More Fun Experiments to Try

Explore states of matter , phase changes and water experiments with these activities below…

• Water Cycle In A Bag
• What Makes Ice Melt Faster?
• Solid, Liquid, Gas Experiment
• Water Evaporation Experiment
• Frost on a Can Experiment
• Salt Water Density Experiment
• Try Ice Melt Activities with younger kiddos

Helpful Science Resources To Get You Started

Here are a few resources that will help you introduce science more effectively to your kiddos or students and feel confident yourself when presenting materials. You’ll find helpful free printables throughout.

• Best Science Practices (as it relates to the scientific method)
• Science Vocabulary
• 8 Science Books for Kids
• All About Scientists
• Free Science Worksheets
• Science Supplies List
• Science Tools for Kids
• Join us in the Club

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• 90+ classic science activities  with journal pages, supply lists, set up and process, and science information.  NEW! Activity-specific observation pages!
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• Be a Collector activities pack  introduces kids to the world of making collections through the eyes of a scientist. What will they collect first?
• Know the Words Science vocabulary pack  includes flashcards, crosswords, and word searches that illuminate keywords in the experiments!
• My science journal writing prompts  explore what it means to be a scientist!!
• Bonus STEAM Project Pack:  Art meets science with doable projects!
• Bonus Quick Grab Packs for Biology, Earth Science, Chemistry, and Physics

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~ projects to try now ~.

All Science Fair Projects

1000 science fair projects with complete instructions, the effects of salt and sugar on water.

Method & Materials

Why do this project, also consider, full project details, related videos.

Related Science Fair Project Ideas