Archives of Ask A Scientist!
About "Ask A Scientist!"
On September 17th, 1998 the Ithaca Journal ran its first "Ask A Scientist!" article in which Professor Neil Ashcroft , who was then the director of CCMR, answered the question "What is Jupiter made of?" Since then, we have received over 1,000 questions from students and adults from all over the world. Select questions are answered weekly and published in the Ithaca Journal and on our web site. "Ask A Scientist!" reaches more than 21,000 Central New York residents through the Ithaca Journal and countless others around the world throught the "Ask a Scientist!" web site.
Across disciplines and across the state, from Nobel Prize winning scientist David Lee to notable science education advocate Bill Nye, researchers and scientists have been called on to respond to these questions. For more than seven years, kids - and a few adults - have been submitting their queries to find out the answer to life's everyday questions.
Now suppose you took your glass of water from the countertop and sealed it inside a somewhat larger, airtight container. What do you think would happen? If you observe the process over a period of time, you will see the water level drop initially and then (if you started with enough water) evaporation will seem to stop. Your closed system has reached equilibrium: There is enough water vapor in the closed container that molecules are condensing back onto the surface at the same rate as they evaporate. The rate of evaporation is different for different liquids. For instance, alcohol evaporates more quickly than water, while oils takes much longer.
The rate of evaporation also depends on the temperature of the liquid and its surroundings. Some heavy oils (or exotic liquids like liquid mercury) may need to be heated before they show appreciable evaporation.
If you raise the temperature of a liquid enough you can start a process of evaporation within the liquid itself. This process is another very familiar one-it's called boiling!
- Why do scuba divers wear rubber?
- What would happen if I dyed water green with food coloring, then put it in a humidifier? I was going to do it but my mom made me stop at the last second.
- Where does static electricity come from? How does it get in my cat's fur? Why is it worse in winter? How do dryer sheets get static out of clothes?
- If the electrons are attracted to the protons, why don't they come crashing into the nucleus?
- Why does light travel slower in different materials (glass, water, etc.)? Also, how have scientists slowed light to "walking speeds"?
- Does energy have mass? Does light have mass?
- If the mantle can rise when weight has been lifted off of it (isostasy), then why are some islands sinking into the ocean?
- What exactly are isotopes? I know that an element with different proton and neutrons is an isotope. So would it mean that (for example) Barium is an isotope but Aluminum is not?
- How are crystals formed?
- How are submarines able to go down so deep under the water, and then surface?