Monday, January 26, 2015

Episode 250 (1-26-15): Reaching the Boiling Point

CLICK HERE to listen to episode audio (3:52)

Transcript, photos, and additional notes follow below.


TRANSCRIPT

From the Cumberland Gap to the Atlantic Ocean, this is Virginia Water Radio for the week of January 26, 2015.
This week, we have the second of two special episodes on the physical states of water, written especially for Virginia science students in kindergarten to third grade.

You’re about to hear a mystery water sound.  Have a listen for about 10 seconds, and see if you can guess what this sound is.  And here’s a hint: It’s not only rain that can end up as drops.

SOUND – MELTING ICE FROM TREE LIMBS IN BLACKSBURG, VA., JAN. 24, 2015

If you guessed, ice melting from trees, you’re right!  After a night of freezing rain in January 2015 in Blacksburg, Virginia, thin layers of ice coated many tree limbs.  But energy from the next day’s sunshine soon warmed the ice, causing it to melt from a solid into falling liquid drops.

A day or two later, those liquid drops were gone.  Some of th3 drops sank into the ground or ran off into creeks.  But with more heat from the sun, other drops evaporated, that is, they changed into an invisible gas called water vapor.  You might think you can see water vapor when you look at clouds.  But clouds are actually water in the sky that has cooled enough to condense, or turn back into visible liquid water.

What’s a very common place where can you watch and hear liquid water being turned into a gas and back again?  See if you know while you listen for about 10 seconds to this mystery sound.

SOUND – BOILING WATER IN A WHISTLING TEA KETTLE

If you guessed boiling water on a stove, right again!  A hot stove can add enough energy, fast enough, to liquid water to make it boil and give off bubbles of water vapor.  The escaping water vapor makes the tea kettle whistle, but the steam you can see above a whistling tea kettle is no longer water as a gas.  Instead, its water that cooled as soon as it left the kettle and changed back into a liquid.

The normal temperature of boiling water is 212 degrees Fahrenheit, or 100 degrees Celsius.  But sometimes water boils at a temperature higher or lower than that.  For example, in Denver, Colorado, at about 5000 feet above sea level, water boils at only about 200 degrees Fahrenheit.  How come?  That’s a question for YOU to answer.  And here’s a hint: this sound [SOUND - AIR BEING RELEASED FROM A BIKE TIRE] means somebody’s bicycle tire is losing air pressure.  Good luck!

[The answer to the question, not included in the audio: Water boils when the vapor pressure of the water equals the pressure of the surrounding atmosphere; at that point, bubbles of water vapor escape from the liquid water.  Water reaches atmospheric vapor pressure at 212 degrees F or 100 degrees C when the atmospheric (or air) pressure is at what’s defined as “standard pressure” or “standard sea level pressure,” 29.92 inches of mercury.  At higher elevations, like Denver, air pressure is lower, so water will boil at a lower temperature.  For more details, please see the information sources listed below.]

For other water sounds and music, and for more Virginia water information, visit our Web site at virginiawaterradio.org, or call us at (540) 231-5463.  From the Virginia Water Resources Research Center in Blacksburg, I’m Alan Raflo, thanking you for listening, and wishing you health, wisdom, and good water.

SHOW NOTES 
[All Internet addresses mentioned were functional as of 1/26/15]

Ice-covered tree in Blacksburg, Va., January 24, 2015
Ice-covered shrub in Blacksburg, Va., January 24, 2015.
Ice pieces fallen from tree limbs in Blacksburg, Va., January 24, 2015.
Water at full boil on a stove in Blacksburg, Va., January 25, 2015.

Sources for this Episode
Virginia Standards of Learning, Virginia Department of Education, online at http://www.doe.virginia.gov/testing/.

“Kindergarten Science Vocabulary,” VocabularySpellingCity.com, online at http://www.spellingcity.com/kindergarten-science-vocabulary.html.

“First Grade Science Vocabulary,” VocabularySpellingCity.com, online at http://www.spellingcity.com/first-grade-science-vocabulary.html.

“Second Grade Science Vocabulary,” VocabularySpellingCity.com, online at http://www.spellingcity.com/second-grade-science-vocabulary.html.

“Third Grade Science Vocabulary,” VocabularySpellingCity.com, online at http://www.spellingcity.com/third-grade-science-vocabulary.html.

“Water Properties and Measurements,” U.S. Geological Survey (USGS) Water Science School, online at http://water.usgs.gov/edu/waterproperties.html.

“Atmospheric Pressure,” Encyclopedia Britannica, online at http://www.britannica.com/EBchecked/topic/41486/atmospheric-pressure.

“Boiling Point,” Encyclopedia Britannica, online at http://www.britannica.com/EBchecked/topic/71799/boiling-point.

SOLs Information for Virginia Teachers
This episode may help with the following Virginia’s 2010 Science Standards of Learning (SOLs):
Measurements of temperature on metric and English scales (2.1 and 3.1);

Physical properties of matter in different phases (2.3);

Physical properties of water in different phases (K.5);

Energy’s effects on water and water cycle (1.6, 2.3, 3.9)
;
Weather basics (2.6).

Some Related Virginia Water Radio Episodes on Water’s Physical and Chemical Properties

(Teachers: Please note that the episodes listed below were not written specifically for elementary school children, except for Episode 249, which was written for K-3 students.  The episodes may, however, have information or sounds that might help teachers in various grades with water-related topics.)

Physical phases of water |
EP144 – 1/14/13 (ice on ponds), EP199 – 2/3/14 (snow), EP249 – 1/19/15 (ice on streams)


Surface tension | 
EP217 – 6/9/14

Water as a solvent | 
EP93 – 12/19/11; EP210 – 4/21/14; EP236 – 10/20/14

For a subject index to all previous Virginia Water Radio episodes, please see this link: http://www.virginiawaterradio.org/p/index.html.

Friday, January 16, 2015

Episode 249 (1-19-15): At the Freezing Point

CLICK HERE to listen to episode audio (3:23)

Transcript, photos, and additional notes follow below.


TRANSCRIPT


From the Cumberland Gap to the Atlantic Ocean, this is Virginia Water Radio for the week of January 19, 2015.

This week, we have a special episode written just for Virginia’s youngest science students, those from kindergarten to third grade.

You’re about to hear two kinds of mystery sounds.  When you do, see if you can answer this riddle: How are the two the same, but also different?  Here goes!

SOUNDS – 9 SEC - WATER POURED INTO A GLASS, THEN ICE DROPPED INTO THE GLASS

Did you figure this out?  Both sounds were water being put into a glass.  But the first sound was water as a liquid, while the second was ice, or water frozen into a solid.

Now let’s see if you can guess two more kinds of mystery sounds.  Ready?

SOUNDS – 7 SEC - FLOWING STREAM, WITH PIECES OF ICE BEING BROKEN OFF AND SPLASHING INTO THE STREAM

How’d you do this time?  That was the sound of liquid water flowing in a creek, followed by pieces of ice on the creek’s edge breaking off and splashing into the flowing water.

Just like a freezer can turn liquid water into ice cubes, winter weather can often stay below 32 degrees Fahrenheit long enough to freeze some of the water in a pond, creek, river, or even the ocean.  In fact, there are many words for different kinds of ice in those places, like anchor ice, border ice, frazil, plate ice, and one you probably know, icebergs.

Water’s all over the world outside, but all living things have a lot of water on their inside.  The water inside plants and animals that stay outside all winter usually doesn’t freeze.  How come?  That’s a question for YOU to answer. 

[Here are three possible answers, not included in the audio: Creatures have coverings to hold in heat (like people have clothes); some animals can move away from freezing temperature (like people going inside); and the water inside many living things contains chemicals that keep it liquid even below 32 degrees.  See the information sources below for more on these topics.]

Before we finish, let’s try one more pair of mystery sounds, this time about ice safety.

SOUND – 6 SEC - PEBBLES BOUNCING ON ICE-COVERED POND, THEN POND ICE CRACKING AND SPLASHING

Any guesses about what you heard?  The first was small rocks bouncing on an ice-covered pond, but the second was that pond’s ice breaking and sinking.  That’s a reminder that thin ice can hold pebbles, but ice has to be solid and at least about four inches thick to hold people.  So never go out on ice-covered water alone and not unless a grown-up checks it first.  You can still have fun on the bank, seeing how far a pebble can bounce!

SOUND – 3 SEC – PEBBLES BOUNCING ON ICE-COVERED POND

For other water sounds and music, and for more Virginia water information, visit our Web site at virginiawaterradio.org, or call us at (540) 231-5463.  From the Virginia Water Resources Research Center in Blacksburg, I’m Alan Raflo, thanking you for listening, and wishing you health, wisdom, and good water.


SHOW NOTES 
[All Internet addresses mentioned were functional as of 1/16/15]

Ice on Toms Creek, Heritage Park in Blacksburg, Va., Jan. 11, 2015.

Varied patterns in ice formed on a shallow drainage channel in Heritage Park, Blacksburg, Va., Jan. 11, 2015.
 
Air pockets under ice on a shallow drainage channel in Heritage Park, Blacksburg, Va., Jan. 11, 2015.

Thin ice on top of pond in Heritage Park in Blacksburg, Va., Dec. 28, 2012.


Acknowledgments
The stream ice sounds in this episode were recorded at Toms Creek in Heritage Park in Blacksburg, Va., on January 11, 2015.  The sounds of pebbles bouncing on an ice-covered pond and the sound of thin ice breaking were recorded at the Heritage Park pond in Blacksburg on December 28, 2012, and January 13, 2013.  Thanks to passer-by Sam for help in recording the sounds of rocks bouncing on ice.

Sources for this Episode
“Chilling Out, Warming Up: How Animals Survive Temperature Extremes,” by Brian Rohrig, ChemMatters Online Oct.-Nov. 2013 (American Chemical Society), online at http://www.acs.org/content/acs/en/education/resources/highschool/chemmatters/past-issues/archive-2013-2014/animal-survival-in-extreme-temperatures.html

“Eight ways that animals survive the winter,” by Sarah Zielinski, Science News (Society for Science & the Public), Jan. 22, 2014, online at https://www.sciencenews.org/blog/wild-things/eight-ways-animals-survive-winter.

“First Grade Science Vocabulary,” VocabularySpellingCity.com, online at http://www.spellingcity.com/first-grade-science-vocabulary.html.  (The site also has vocabulary for grade levels and other subjects.)
“How Woody Plants Survive Extreme Cold,” Iowa State University, Mar. 1, 1996, online at http://www.ipm.iastate.edu/ipm/hortnews/1996/3-1-1996/brr.html.

“Ice Safety,” Minnesota Department of Natural Resources, online at http://www.dnr.state.mn.us/safety/ice/index.html.

“Ice Terminology,” Lake Superior-Duluth Streams.org, online at http://www.lakesuperiorstreams.org/understanding/iceterms.html.

Where They Go in Winter, by M. W. Buck, Abingdon Press, Nashville, Tenn., 1968.

Some Related Virginia Water Radio Episodes on Water’s Physical and Chemical Properties
(Teachers: Please note that these episodes were not written specifically for lower elementary school children.  They may, however, have information or sounds that might help teachers in those grades with water-related topics.)

Ice on ponds | EP144 – 1/14/13
Snow physics/chemistry | EP199 – 2/3/14
Surface tension | EP217 – 6/9/14
Water as a solvent | EP93 – 12/19/11; EP210 – 4/21/14; EP236 – 10/20/14

For a subject index to all previous Virginia Water Radio episodes, please see this link: http://www.virginiawaterradio.org/p/index.html.

SOLs Information for Virginia Teachers
This episode may help with the following Virginia’s 2010 Science Standards of Learning (SOLs):
Adaptations: 3.4;
Habitats/niches: 1.4 (plant needs and characteristics), 1.5 (animal needs and characteristics);
Physics/chemistry of water in different states (K.5, 2.3);
Seasonal weather changes (1.7, 2.5, 2.7).