You can stress that when you use heat energy, you need a temperature difference by using a cold water wettened napkin on the small top bulb without touching the bottom. Hint that heat causes pressure to rise and gas to expand by holding the filled top bulb until it empties and bubbles leave at the bottom end.
Wrap a hand about each end simultaneously, and control the flow. May 29, Students find these fascinating and then we use them for a distillation lab first and then to study vapor pressure later in the year.
My 8-year-old son had a "Mad Scientist" birthday party, so I ordered a hand boiler for him. It is amazingly fun. He showed the kids who oooed and ahhhed, let them have a turn, and returned to it throughout the day. It is so fascinating that my husband took it to work the next day to show his co-workers! I am going to buy a few more! The hand boilers are a great tool as a hook when teaching equilibium. Also, they are great at demonstrating phaze equilibrium. When used correctly, they are quite sturdy.
May 27, The Hand Boiler is, definitely, the classroom favorite We've had a lot of laughs when I've called a couple of students up to demonstrate their "heat quotient"--its funny because, for some, the liquid barely moves, and for others, it boils in just a few seconds!! My students love my science "toys" and enjoy being able to apply what we learn in class to explain what is happening and why!
Students use the hand boiler for the survey of gas properties lab. They are fascinated, and have broken only one during five years of use. This is a great little demo that I have used to help show that boiling point is a physical property and a physical change! Quick and easy and the students are immediately engaged!! May 18, May 16, I just finished using the hand boiler with an elementary teacher workshop.
The participants loved it and learned about the expansion of gases, too. The only issue is the title. Make sure your students know that the phenomenon involves the expansion of gases rather than the boiling of the liquid.
I have always used handboilers to demo pressure, density and vaporization, even when doing water cycle. They ae great to open with as a question of why? In stead of going to the mall into a novelty store, I can get one along with other ordered products.
Was afraid hand boiler would be fragile, but it was well made. Fun to play with too! This is a great discussion tool that occupied my AP chemistry students for a very engaged discussion.
This hand boiler is a great classroom toy and serves as a great demonstration for gas laws and pressure. Elementary Middle School High School 4-PS Students can use the Handboiler to make observations to provide evidence that energy can be transferred from place to place light and heat sources.
Pretty fascinating science toy and an excellent demonstration of energy transfer. Comes in four different colors: blue, green, purple and red - let us pick one for you. The colored liquid in the boiler is comprised of a volatile mixture of liquids Methylene Chloride that have a boiling point just above room temperature.
The body heat from your hand causes the liquid to boil, which in turn makes the liquid evaporate, turning it to gas. The expanding gas pushes the liquid upwards and when you release your hand, equilibrium is re-established.
The gas condenses into a liquid again and flows back into the lower bulb. As you probably know, water boils at a temperature of about degrees Celsius. With a hand boiler, the temperature of your hand is enough to cause the liquid to bubble and appear to boil. Check out a video of a hand boiler: When holding the bottom of the boiler with your hand, the liquid inside becomes exposed to the heat of your hand and it begins to evaporate.
Its pressure increases and the liquid expands. As a result it shoots up the glass tube and settles in the top bulb, since it cannot go any further.
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