A thermometer is a device that measures the temperature of an object or a substance. There are different types of thermometers, such as digital, infrared, or mercury thermometers, that use different methods and principles to measure temperature. However, you can also make your own DIY thermometer at home with some simple materials and a little bit of science knowledge. In this article, we will show you how to make a DIY thermometer that can measure 95 celsius and fahrenheit using water, rubbing alcohol, food coloring, a straw, a bottle, and some clay.
The materials you need
To make your DIY thermometer, you will need the following materials:
- A clear plastic or glass bottle with a narrow neck. You can use an empty water or soda bottle for this purpose.
- A clear plastic straw that fits inside the bottle’s opening. Make sure the straw is straight and not bent or curved.
- Some water and rubbing alcohol. You will need equal amounts of both liquids, about 1/4 cup each.
- Some red food coloring to make the liquid visible and resemble the mercury in a traditional thermometer.
- Some modeling clay or playdough to seal the bottle’s opening and hold the straw in place.
- A permanent marker to mark the temperature scale on the bottle or the straw.
The steps to follow
To make your DIY thermometer, follow these steps:
- Mix the water and rubbing alcohol in a measuring cup. You can either use cold or room temperature water for this step. Stir well until the liquids are well combined.
- Add a few drops of red food coloring to the mixture and stir again. The more drops you add, the darker the color will be. You can also use other colors if you prefer, but red is more visible and resembles the mercury in a traditional thermometer.
- Pour the colored liquid into the bottle until it is about 1/4 full. You don’t need to fill the bottle completely, as you need some space for the liquid to expand and contract with temperature changes.
- Insert the straw into the bottle’s opening and push it down until it is submerged in the liquid, but not touching the bottom of the bottle. If the straw touches the bottom, the liquid won’t be able to move up and down inside it and your thermometer won’t work.
- Wrap some clay around the top of the straw and the opening of the bottle to seal it tightly. Make sure there are no gaps or holes where air can escape or enter. Also, make sure the top of the straw is not covered or pinched by the clay, as you need to see the liquid level inside it.
- Use a permanent marker to mark the liquid level on the bottle or the straw when it is at room temperature. This will be your reference point for measuring temperature changes. You can also write down the actual room temperature next to the mark if you have another thermometer to compare with.
- To measure 95 celsius and fahrenheit, you will need to place your DIY thermometer in a container of hot water that has been heated to that temperature. You can use a pot of boiling water on a stove or a microwave-safe bowl of water in a microwave for this purpose. Be careful not to burn yourself when handling hot water and use oven mitts or gloves for protection.
- Carefully place your DIY thermometer in the container of hot water and watch how the liquid level rises in the straw as it expands due to heat. Wait for a few minutes until the level stops moving and then mark it on the bottle or the straw with a permanent marker. Write down 95°C next to the mark if you are using celsius scale or 203°F if you are using fahrenheit scale.
How does it work
Your DIY thermometer works on the principle of thermal expansion and contraction of liquids. When liquids are heated, they expand and take up more space. When they are cooled, they contract and take up less space. This causes them to move up and down inside a container that has a fixed volume, such as a bottle.
Rubbing alcohol has a lower freezing point and a higher boiling point than water, which means it can withstand more extreme temperatures without freezing or evaporating. This makes it suitable for making a DIY thermometer that can measure both hot and cold temperatures.
When you mix water and rubbing alcohol together, you create a solution that has an intermediate freezing point and boiling point between those of pure water and pure alcohol. This solution can also expand and contract with temperature changes, but not as much as pure alcohol or pure water.
By adding food coloring to the solution, you make it easier to see how much it expands and contracts inside the straw. The straw acts as a narrow tube that magnifies the movement of the liquid due to temperature changes.
By sealing the bottle’s opening with clay, you create an air-tight environment that prevents air from entering or leaving the bottle. This ensures that the pressure inside the bottle remains constant and does not affect the movement of the liquid.
By marking the liquid level at room temperature, you create a reference point for measuring temperature changes. By placing your DIY thermometer in a container of hot water, you expose it to a higher temperature than room temperature and cause the liquid to expand and rise in the straw. By marking the liquid level at 95 celsius or fahrenheit, you create a scale for measuring that temperature.
The limitations and applications
Your DIY thermometer is a fun and simple science project that can help you learn and understand how thermometers work and how to measure temperature. However, it also has some limitations and applications that you should be aware of.
- Your DIY thermometer is not very accurate or precise. It can only measure temperature changes in a rough way and it can be affected by various factors, such as the quality of the materials, the amount of liquid, the size of the straw, or the air pressure. It can also have some errors or variations due to human factors, such as how you mark the liquid level or how you read the scale.
- Your DIY thermometer is not very durable or reliable. It can break or leak easily if you drop it or handle it roughly. It can also lose its color or clarity over time due to evaporation or contamination. It can also be affected by external factors, such as sunlight, humidity, or dust.
- Your DIY thermometer is not very safe or sanitary. It contains rubbing alcohol, which is flammable and toxic if ingested. It also contains food coloring, which can stain your clothes or skin. It also contains clay, which can harbor bacteria or mold. You should always wash your hands before and after handling your DIY thermometer and keep it away from children, pets, or sources of heat or fire.
- Your DIY thermometer is not very practical or useful. It can only measure temperature in a limited range and it can only measure one temperature at a time. It can also only measure the temperature of liquids, not solids or gases. It can also only measure the temperature of the container it is placed in, not the surrounding environment.
- Your DIY thermometer is more suitable for educational or recreational purposes than for scientific or professional purposes. It can help you learn about thermal expansion and contraction, temperature scales, and how thermometers work. It can also help you have fun with science experiments and activities at home or in school.
Making a DIY thermometer that can measure 95 celsius and fahrenheit is a simple and fun science project that you can do at home with some basic materials and a little bit of science knowledge. You can use water, rubbing alcohol, food coloring, a straw, a bottle, and some clay to create a device that can measure temperature changes by using thermal expansion and contraction of liquids. You can also use a permanent marker to mark the temperature scale on the bottle or the straw.
However, your DIY thermometer also has some limitations and applications that you should be aware of. It is not very accurate, precise, durable, reliable, safe, sanitary, practical, or useful. It is more suitable for educational or recreational purposes than for scientific or professional purposes.
By knowing how to make a DIY thermometer that can measure 95 celsius and fahrenheit, you can easily compare and understand different temperature units and scales.