Thursday, October 2, 2014

Hydrogen is a chemical that all by itself is a gas in the air.
There is more hydrogen in the universe than any other type of element!

Many types of molecules have hydrogen in them.
Like water is hydrogen and oxygen.
A very strong dangerous acid is hydrochloric acid, made from hydrogen and chlorine.
A chemical sometimes used for cleaning is hydrogen peroxide, which is hydrogen and oxygen.
In the sun's core, hydrogen is part of what makes all the energy for the sun.
There is a type of battery called a hydrogen fuel cell that uses hydrogen to help make energy.

There are many uses for hydrogen, it's a good thing there is so much of it!

Thursday, September 11, 2014

Oxygen might just be the most important element for humans on the whole planet.

The air we breathe has oxygen that goes into our lungs, which is carried off to parts of our body in our blood.

Water is made up of the chemicals hydrogen and oxygen.

When you burn wood in a fireplace, the fire needs oxygen to keep burning.

And remember that all elements can be gas, liquid or solid depending on how hot or cold they are?

Liquid oxygen is super cold, almost -300 degrees!
When we sent a space shuttle up into outer space, we used a huge tank full of liquid oxygen to burn because it is such great fuel.
(from: wikipedia - oxygen)

Thursday, September 4, 2014

Potassium is another metal that is found on the earth.
It is very soft, and can easily be cut with a knife.

If you put potassium in a glass of water, it will make a big explosion!

When the potassium is in the water, it mixes up with hydrogen and oxygen.
As it is mixing together, the chemicals let off a lot of heat.
With all that heat, some of the hydrogen gas lights on fire, and then it goes kaboom!

We have potassium in our bodies, but it's not the same as the potassium metal that explodes.
It's sort of like what's left from the mixed up potassium after the big explosion, so it's safe.
(from: wikipedia - potassium)

Thursday, August 21, 2014

When you drink milk, did you know that you're also drinking some metal?
Calcium is a healthy ingredient found in milk, that helps us have strong bones and teeth.
You can't tell that it's metal because there's only a tiny bit of calcium in there, so little you can't even see it.

Thursday, June 5, 2014

Iron is a very common mineral found throughout the earth, and it is used in many types of metal things.

Because it is such a useful metal, it is mined throughout the world.
(from: wikipedia - iron)

When combined with other types of minerals like carbon, it can become stronger.
When two minerals are combined like that it is called an alloy.
With the right type of carbon and iron, you can make the super strong metal steel.

Thursday, May 1, 2014

We just learned that rocks are made up of minerals, and that minerals are the building blocks of the world.

One type of mineral is called pyrite.
It is a shiny metal that looks so much like gold that people called it fool's gold because people would discover it and think they had real gold and were rich.
(from: wikipedia - pyrite)

Thursday, June 20, 2013

To help remember all of these different things, a scientist came up with something called the periodic table.
It takes all of the different chemical elements and puts them into a picture, organized by their atomic number.
Each element has it's own short name, like Oxygen is O, Hydrogen is H, Neon is Ne.

Thursday, May 16, 2013

We learned before about Earth's gravity and how it pulls you to the ground.

The reason it does that is because of something called mass.

Mass is sort of like how heavy something is, but also how big it is.

So a marshmallow as big as a house may be heavy enough to squash you,
but if you had a marshmallow as big as a bowling ball, the bowling ball is heavier.

A bowling ball is pretty heavy, but a bowling ball the size of a penny would be pretty light.

The two things that work together for mass are size and something called density.
Density is another big word that means something like how thick a thing is for it's size.

If something has really big size and density (like Earth) then it has really big mass.
If it is big but fluffy like a cloud, it has small mass.
If it is small but really thick density like a marble, it has small mass.
And if it is small and fluffy like a marshmallow then it has really small mass.
(from: wikipedia - earth)