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Ask Janice

Page history last edited by Janice VanCleave 7 years, 7 months ago





Hi, I am Janice VanCleave.

Mr. Parker has invited me to be part of your class wiki.
Since I write science books, I'll answer questions you have about science.


I'll try to check this page often for your questions, but if you are in a big hurry, ask Mr. Parker to send me an email to remind me.


Check the different sciences listed below for questions that were asked last year.  


It helps if I know your name, so when you ask a question, the name Mr. Parker as instructed you to use on this wiki.


I look forward to sharing science ideas with you.

Janice VanCleave


       Ask Janice About:

     Astronomy    Biology

           Chemistry       Earth Science

        Ecology               Engineering


          Human Body  Plants







Janice VanCleave is the author of 50 + books about science and math like the ones pictured above and she is waiting for your questions. Simply type your question in the first column, wait a few days, and Janice will answer in the second column. Look at the marquee below for ideas.

Why are Popsicles softer than ice? What makes bananas turn brown? Why does the Moon seem to change shape? Where does the voice on the radio come from? What makes a smoke bomb smoke? How do whales use sound to "see"?






Type your question here! Don't forget to put your name here too

Janice will answer you here!

How did we americans come up with the currency we have today? Levi   http://www.kids.gov/k_5/k_5_money.shtml  
Is it true if a gaint fish under water can create a vacum when it opens its mouth?Neil  Yes, but they don't have to be giants. The Chaca is ready to strike, it opens and closes its large mouth rapidly, creating a vacuum that pulls in water as well as fish swimming too close. Sometime very large fish, up to half the Chaca's own length is pulled in. Chaca are also able to use their large mouth as a means of propulsion; when frightened, they will gulp a large amount of water and expel it through their gills.
What does A.M. and P.M. stand for? Sean  

What does A.M. and P.M. stand for? Sean

“AM” stands for the Latin phrase Ante Meridiem —which means “before noon”—and “PM” stands for Post Meridiem : “after noon.”


how do animals adapt to the season? Alaysha 

Adapt is to make suitable to or fit for a specific use or situation.

Adaptation is the act or process of adapting;  the state of being adapted; adjustment to environmental conditions; modification of an organism or its parts that makes it more fit for existence under the conditions of its environment.

The coloring and texture of an organisms surface so that it blends in with its environment provides protection from its prey. This type of natural adaptation is called camouflage.

Animals with fur generally shed a lot of their hair before summer and their hair grows thicker before winter. The fur of some animals, such as snowshoe hares rabbits, changes color during different seasons. In the

The snowshoe hare shown in the photo has large feet, black-tipped, relatively small ears. In summer, the hare is dark brown with its small tail dark on top and dusky to white underneath. In winter, the hare's fur is white on the tips but remain dark at base. The coloring of the hare camouflages it so that is blends in with its environment, making it more difficult for predators to find it.

 Some animals, like squirrels, mice and beavers, gather extra food in the fall and store it to eat later. Squirrels and mice may huddle close together to stay warm. Mice build tunnels through the snow. This allows them to stay warmer as they travel from place to place.

Some  animals eat different kinds of food during different seasons. For example, the red fox eats fruit and insects in the spring, summer and fall. In the winter, these foods are not available, so instead the red fox eats small rodents (rats).

Why are fossil fuels so rare?Levi 

Why are fossil fuels so rare?Levi

Fossil fuels are not rare. There is still a large amount of fossil fuels, such as coal and oil. Some of these fuels may be difficult and/or expensive to recover. There is still a lot of fossil fuels. Scientists are searching for other types of fuels that do not pollute the air as much as do fossil fuels. Thus, some hybrid cars use both fossil fuel as well as electric energy from a battery. There are wind generators and solar panels from which energy is obtained. Nuclear energy is also an alternative source of energy. Alternative energy sources will be something that you will see changing and maybe something that you will discover in your future career.

When we mix colors, why does it make another color?Misa 

Mixing paint colors does not cause a chemical reaction, so what you have is a mixture of the separate colored particles. Light reflecting from these color particles enters your eye which sends a message to your brain. Here the combination of the two separate color particles is interpreted. If you mix yellow and blue paint, the brain interprets this as green. Use a magnifying lens to look at the colors in a newspaper. What looks like green is actually tiny dots of yellow and blue. What appears to be orange is made of tiny dots of red and yellow.

Why does color spred out on water and cloth? Alaysha 

Alysha, I assume you are talking about liquid colors spreading out on cloth. Many clothes are made of tiny fibers woven together. These fibers form microscopic pathways for the liquid to move through, much like it does in a paper towel, which is made up of wood fiber-tunnels.

Now about spreading out on water---do you mean on the surface of water? This would only happen if the liquid color is not soluble in water. Like pouring liquid cooking oil on water--the oil floats on top.

But is you mean the coloring spread throughout a container of water, this is different. The coloring has to be soluble in water, meaning it will mix with the water forming a solution. If you pour dry strawberry Kool-Aid into a large container of water,  some of the red powder dissolves as soon as it touches the water, some sinks to the bottom of the container. If you keep the container very still--no shaking, the red powder will in time spread throughout the water so that all of the water is the same color. This is called diffusion, which mean a natural spreading until there is an equal amount throughout. Diffusion occurs because of the movement of particles -the particles of Kool-Aid are solids and they do not move very much. Actually, they basically stay in one position and vibrate a little--the vibrate faster at higher temperatures. It is the water that causes the mixing. The molecules of water are able to move more --it is not like a gas molecule that keeps moving until it strikes something and then bounces in another direction. Instead, water molecules just move more out of place than do solid particles. As the water molecules move they move the solid particles. There is a bit more science involved, but you will learn this later in chemistry.

Why does the coke blow up when you put mentos in it? Bien 

The mentos candy causes the carbon dioxide gas dissolved in the soda to quickly leave the liquid. This results in the bubbles of gas quickly collecting and creating a force that pushes the gas bubbles along with the liquid soda out the small opening of the bottle. It is the surface of the candy that is significant. The surface is very porous--has tiny indentation in which the carbon dioxide gas can easily collect in. Fruit-flavored Mentos with a smooth waxy coating were tested and they did not cause the soda to erupt.

I wonder--what would happen if you poured the coke in a large bowl and dropped the mentos in the soda? Would it spray up like it does when the soda is in a bottle with a small opening?

Why does oil and water not mix? austin    Austin--you can mix oil and water --meaning to pour both into the same container. When you stir or shake the container the two liquids might appear to temporarily form one substance, but actually they are only temporarily blended  because they are immiscible, which means the liquid do not form a solution. Substance only form solutions if they have an attraction for each other. Water is attracted to salt as well as to sugar particles. Water is not attracted to oil, thus they do not form a solution, instead particle of water and oil make an effort to separate from the other. The oil spill in the ocean had different kinds of oil, some of it floated on the surface of water because and other types floated below the surface and some on the ocean floor. But the oil grouped together in globs unless something stirred it and cause it to separate--like shaking a container of oil and vinegar with spices. At first the content of the container is all mixed together--not a solution --but let the container set still and the oil and water (vinegar is mostly water) separate.
Why do igneous rocks come from volcanos? Sean
Igneous rocks are produced when rock materials melt and mix together. Since molten rock is formed inside volcanoes due to the extreme temperatures, when this molten material reaches the surface it is called lava. Under the Earth's surface the molten rock is called magma. If the magma cools very slowly, generally underground, large crystals form in the rock. If the magma cools quickly, above ground the crystals that form are much smaller.
How does soap clean things? austin

Soap molecules are bipolar--meaning one end has an attraction for water and the other end attract oily substances--Dirt that will dissolve in water doesn't really need the soap, but things that do not readily dissolve in water will be more likely to be attracted the hydrophobic (oil attracting end of the soap molecule). Then the opposite end of the soap molecule called the hydrophillic end (water loving end) attaches to a water molecule. Now you have soap scum which is goes out with the wash water.

 Why is the abreviation for gold AU and the signal for potassium K?

 K = Potassium = Kalium


Au = Gold = Aurum

How does a atomic bomb explode? Mathew

The plutonium is unstable, or radioactive. This means the atoms on their own are constantly 'falling apart', breaking up into smaller elements that are more stable.

This is called radioactive decay.


Every time one plutonium nucleus decays, it releases energy, neutrons, and two smaller atoms that are more stable. The released energy is called radiation that is damaging to living cells.This spontaneous decay of plutonium produces heat, but this is not an explosion.


An atomic bomb could have either uranium or plutonium. The atomic bomb used in WW II had an outer covering of an explosive material called TNT.


When the TNT exploded, it squeezed the plutonium into a very dense mass, called "critical mass." The plutonium is now so densely packed together that the neutrons escaping from the decaying nuclei of plutonium cannot escape from the plutonium without bumping into another plutonium atom! These atoms decay giving off more neutrons that bump into more plutonium nuclei and so on.

Within a very tiny fraction of a second, all the nuclei in the chunk of plutonium have been hit by escaping neutrons, and have broken down. The combined energy released from the decay of trillions of plutonium nuclei decays is all released at once! This is a massive quantity of energy; the atomic bomb dropped on Hiroshima in WWII was an example of this process.

Why is cold air more dense than hot air? austin Cold air molecule have less energy and move much slower  than do hot air molecules. The fast moving hot air molecules move farther away from each other. This causes the cold air molecules to be closer together and the hot air molecules to be farther apart. If you collected one jar of hot air and one jar of cold air. The jar with the cold air would have more air molecules, thus more mass. Since density for the air in each jar is the amount of mass (amount of matter--amount of molecules) in each jar, the jar of cold air would be more dense.
Why do animals decay into the ground. austin Living organisms in the ground, called decomposers, feed on the dead animals. For information about decomposers,such as bacteria and fungi, see Geography4Kids. 
Is a sting ray just a flatten shark and if it is how did it get flat?Neil  No, stingrays are not flat sharks--but stingrays are in the shark family. You can find out more about stingrays on this Kids
National Geographic Website.
Why are some crystals called"Liquid crystal?" alaysha Liquid crystals have physical properties between solid crystals and a liquid. Thus, they are called liquid crystals. I realize that this answer seems a bit lame, but you can find out more about this type of matter on How Stuff Works. 
How does the Cape Sundew eat? Sean http://scienceprojectideasforkids.com/2012/sundew-carnivorous-plants/http://scienceprojectideasforkids.com/2012/sundew-carnivorous-plants/
How does the plant pitcher eat and digest? Sean  Sundew plants are carnivorous, meaning they each animals. The leaves of these plants are so sticky that insects get stuck to them. The leaves have chemicals that digest the insects. when an insect gets stuck to a leaf, it wiggles trying to get lose. This motion triggers a motion of the leaves so that the leaf slowly wraps its small tentacles that cover the leaf around the bug. In some varieties, the entire leaf also moves to engulf the bug and turn it into a meal. The bug is then digested on-site and its nutrients are absorbed, giving the plant vital Nitrogen that it can use to grow.
How do clouds make lightning and thunder?Neil  Scientists are not 100% sure why clouds become charged during a thunderstorm. I've read that ice particles in clouds lose electrons as they rub together as wind moves the clouds around. The negative electrons build up in the clouds and the discharge of the negative charges as they move toward the Earth is lightning. 
What is the main difference of baking soda and epsom salt?Titus  Baking soda is the chemical sodium hydrogen carbonate. Epsom salt is the chemical Magnesium sulfate. 
How does the difference between baking soda and epsom salt effect making stalactites and cave coral?Titus  Epsom salt is used to model how stalactites are formed, but the  stalactites are are made of calcium carbonate. Carbon dioxide from the air and water form a weak acid called carbonic acid. This acid seeps through the ground and slowly dissolves minerals made calcium carbonate. As the water drips through the ground into a cave cavity, some of the calcium carbonate starts to build up and some drips onto the cave floor below.  In time, more and more particles of calcium carbonate are deposited  and a stalactite hands down and a stalagmite grows upward from the cave floor.
How does the group of elements called Metalloids react when mixed with other elements? Titus 

Metalloids have metallic and nonmetallic properties.

A metal atom tends to lose valence electrons, which are electrons farthest from the atom's nucleus (center).

A nonmetal atom tends to gain electrons, adding them to the area farthest from the atom's nucleus (center). 

Sulfur is a metalloid. When Sulfur reacts with a metal, the sulfur has more nonmetallic properties. Such as Sodium Sulfide

When sulfur reacts with a nonmetal, the sulfur has more metallic properties. Such as Sulfur Oxide,

 How does the group of elements called Lanthanides react when mixed with other elements?Titus

  • Silvery-white metals that tarnish when exposed to air, forming their oxides.
  • Relatively soft metals. Hardness increases somewhat with higher atomic number.
  • Moving from left to right across the period (increasing atomic number), the radius of each lanthanide 3+ ion steadily decreases. This is referred to as 'lanthanide contraction'.
  • High melting points and boiling points.
  • Very reactive.
  • React with water to liberate hydrogen (H2), slowly in cold/quickly upon heating. Lanthanides commonly bind to water.
  • Burn easily in air.
  • Many rare earth compounds fluoresce strongly under ultraviolet light.
  • The lanthanides react readily with most nonmetals 

What elements make up Superfluid Helium?Titus 

Superfluid Helium is made up of the Helium element that is at a very cold temperature. The colder the temperature the more fluid is this

element. Fluid means to flow. The super-cooled helium gas turns to a liquid and because the attraction between the Helium atoms is so small, their is  very little friction when the atoms move past each other. This superfluid does strange things, such as climb up the walls of its container ==

What elements make up Chlorine Gas?Titus 

Titus, Chlorine gas is made of the chlorine element which is a diatomic molecule. This means that chlorine gas naturally exists with two atoms of chlorine linked together. 


Where is plasma found and can it be used in or as a weapon?Neil                                          Plasma is another state of matter formed when a gas is heated. Heating a gas causes some of its electrons to either be lost or electrons from other atoms to be gained. When electrons are lost or gained by atoms they are charged, which is also called ionized. Plasma is the most common state of matter. All stars are made of plasma and the space between stars is a very low density plasma. Lightning, the auroras, the ionosphere layer of Earth's atmosphere is plasma.  I only found info that says weapons firing plasma are only part of fantasy videos and stories. But, this is not to say that these types of weapons are not being designed and tested.

How do ocean mine when planted stay on the ocean floor?Neil


Are you talking about objects that blow up? If so, they have to be weighted. But I am not familiar with such objects being placed on the ocean floor.
Why when warm air and cool air hits each other they cause a tornado? Austin


  When Warm moist air shoots upward meeting colder, dryer air.  Warm moist air is lighter than the cold dry air making for a strong updraft within the thunderstorm. As the warm moist air rises, it may meet varying wind directions at different altitudes. 

If these varying winds are staggered in just the right manner with sufficient speed, they will act on the upward rising air, spinning it like a top.   The storm will begin to show visible rotation, often forming a wall cloud. Inside the storm these spinning winds can begin the formation of a tornado, which is called a mesocyclone. Only about 30 percent of mesocyclones actually produce a tornado, but about 95 percent produce severe weather.

Why is snow white? Austin   Austin,
why does your eyes change colors when you take a picture in the dark?makena First the camera flashes and the light enters your eye and shines on the red blood vessel on the inside of your eye. Red light is reflected from these red vessels
Second, the camera takes the picture and the pupil of your eye (the dark hole) has a red color because of the red light from the blood vessels.  
Why when people are younger their heart beats faster? Austin  

What is maximum heart rate?

The maximum heart rate is the highest heart rate achieved during maximal exercise. One simple method to calculate your predicted maximum heart rate, uses this formula:

220 - your age = predicted maximum heart rate


Causes for Lower heart rate in elderly

Aging leads to a general weakening of the heart, which can cause a slow heart rate. Other causes often associated with the elderly include the after-effects of a heart attack, low thyroid production, high blood pressure, heart infections and inflammatory disorders. The medications prescribed to manage these conditions can also be the cause of a slow heart rate. For example, drugs designed to lower blood pressure can also lower heart rate.

Why is fat only in unhealthy food? Austin Not all fat is unhealthy, Unhealthy food? Depends on what you are eating and how much you are eating. Also depends on your own health. I am diabetic, so I must be careful about the amount of fat that I eat because the human body turns fat into sugar. Food that are fried in fat are more fattening. So if you are counting calories, eat fewer fried foods. Fat is in milk and milk is healthy, fat is in butter, which is healthy. Nuts, such as almonds and pecans have fat and they are healthy. Generally, food is considered unhealthy if you eat too much.
How does the sun make evaporation? Austin
The light energy from the Sun warms the surface of liquid water causing the water molecules to heat up and start moving faster. At first the water molecules are linked together. When a water molecule moves fast enough it breaks away from the other water molecules and escapes into the air By itself the water molecule is in gas form. The change from a liquid to a gas is called evaporation.  

what does the pyramid with the eye on the dollar bill mean ? Titus 

Why can't we have just one big season?Bobby   
Why did the Americans take out the two dollar bill?Neil  
Why did the government give out  the 10,000 dollar bill? Sean   
What is a solution to chocolate?Alaysha   

what is this?

My dad and I were cleaning the back yard and this was on the leaf my dad tried to research what it was but it never came.


Why is fire so hot and burns us?-Alexis   
What would happen if water lost the oxegen and it was just hydrogen? Mae  



Comments (15)

steve parker said

at 1:26 pm on Sep 1, 2009

What does decidous mean? destiny

Janice VanCleave said

at 5:04 am on Sep 2, 2009

Plants that loose all their leaves during part of the year are called DECIDUOUS. Plants that do not lose all of their leaves during the year are called EVERGREEN.
Janice VanCleave

Lisa said

at 1:09 pm on Sep 18, 2009

Thankyou for answering my quetion.Lisa

Brenna said

at 1:56 pm on Sep 21, 2009

you are relly cool

Lizzie said

at 8:29 pm on Sep 24, 2009

Thank you for answering my question.Elizabeth

Casey said

at 6:39 pm on Oct 1, 2009

Thats cool that they use bread to erace.

Rosemary said

at 6:53 pm on Jan 19, 2010

Mr.parker can you get us more spases.rosie

alex said

at 10:12 am on Nov 9, 2010

thank you for answering but i do not get it

austin said

at 7:40 pm on Oct 28, 2011

Why didn't you get my answer?

titus said

at 8:00 pm on Dec 16, 2011

Dear Janice Vancleave,
The page has run out of boxes. Would you mind putting some more boxes?

titus said

at 7:32 pm on Dec 24, 2011

I wonder if Janice is okay because she has recently not answered any questions.

neil said

at 9:35 am on Feb 1, 2012

thank you for answering my thingey

austin said

at 7:42 am on Mar 16, 2012

Janice can you please awnser my question now? I have been waiting for a little while.

alaysha said

at 12:13 pm on Nov 18, 2012

Dear Janice Vancleave,
Please try to hurry to answer my question because I want to know really bad!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

claire said

at 10:15 am on May 19, 2015

Dear Janice Vancleave.
You have not been on for a long time and I think you will not be on again.
I really would like you to answer one question! SO just please get on!

You don't have permission to comment on this page.