Structure of Matter

Scientists who explore space recognize similarities among matter on Earth and matter in the solar system. For example, all of the objects in the universe, including Earth and everything on Earth, are made up of tiny particles too small to be seen, called atoms. In this first lesson of the unit, students model an atom to observe the building blocks of matter.

• Science is the search for explanations about the natural world.
• All matter is made up of tiny particles called atoms that are too small to see. An atom is the smallest piece of matter that has the properties of an element. An element is a substance made up entirely of one kind of atom.
• Atoms are extremely tiny, but they themselves are made up of smaller particles, called protons, neutrons, and electrons.
  
  

• Why is curiosity such an important part of science?
• How do scientists gather information about the world around them?
• How is science different from other subjects, such as history or English?
• What is the relationship between the number of protons, neutrons, and electrons that an atom generally has?
• Why do electrons stay in different shells?
• Why do different elements have different properties?
• How are air, the sun, and a tree all similar?
• How can air be considered matter even though we can’t see it?
• If both the sun and air are made up of atoms, how can they be so different from each other?
  
  

Misconception: Only Earth has gravity.

Fact: All matter has gravity. All objects near Earth’s surface are pulled on by Earth’s gravity because Earth is the most massive object near us.

Misconception: Earth doesn't move in the solar system. 

Fact: The sun’s gravity keeps Earth and the other planets in orbit.

Misconception: If an object is at rest, no forces are acting on it.

Fact: Forces are constantly acting on objects both at rest and in motion. 

Atom : the smallest piece of matter that has the properties of an element; a combination of three subatomic particles: protons, neutrons, and electrons

Cause and Effect : a relationship between events or things, where one is the result of the other

Force : a push or pull that acts on an object, changing its speed, direction, or shape

Gravity : a force of attraction between all matter

Mass : a measure of the amount of matter that makes up an object; a property of matter

Matter : everything that has mass and takes up space

Pattern : something that happens in a regular and repeated way

Scale :the size, extent, or importance (magnitude) of something relative to something else

Science : all knowledge gained from experiments

Matter in Space

Scientists have learned that the planets, stars, and other objects in space share some characteristics. For example, they are all made of matter. Matter is everything that has mass and takes up space. The sun and moon are made of matter. Even the air around you is a collection of different kinds of matter.

Matter is made up of tiny parts that are too small to be seen. These parts are called atoms. Many billions of atoms make up even a single grain of sand. Atoms can join together in different ways. The different ways that atoms join together make all of the matter in the universe. Two or more atoms joined together are called molecules.

An element is a substance entirely made up of one kind of atom. Helium gas is an element. Hydrogen is another element. Hydrogen and helium are the main elements that make up stars. There are 118 different kinds of elements. Each element has its own properties.

Scientists work with elements and not atoms. Nobody has ever seen a single atom. They are so tiny and fast that no camera has been able to take a good picture.

Think about a grapefruit. If each atom in the grapefruit were the size of a blueberry, the whole grapefruit would be the size of Earth. There are so many atoms in just one grapefruit that they are impossible to count. Imagine having to fill up the entire planet with blueberries. That’s about how many atoms are in one grapefruit.

In this lesson, students create a large-scale aluminum atom model to observe the basic structure of an atom. Students use their atom models to explain how all matter that we can see, including air and water, is made up of tiny particles that we cannot see.