Chapter 6 : Atoms and Matter
Atoms are the basic building blocks of matter that make up everyday objects
All substances are made up of tiny units called Atoms.
If we want to create a language, we'll need an alphabet. Likewise if we want to create matter we need elements that are made from atoms.
Everything from water to air to solid objects are built from atoms, it is the smallest unit.
Atom consists of a dense central nucleus surrounded by a cloud of negatively charged electrons.
The atomic nucleus contains a mixture of positively charged protons and electrically neutral neutrons.
Likewise, a group of atoms can remain bound to each other, forming a Molecule
Topics covered in this snack-sized chapter:
Matter is generally considered to be anything that has mass and volume.
The "stuff" in the world can be roughly divided into matter and energy. Matter has mass and exhibits gravimetric properties
Matter is thus a general term for the substance of which all observable physical objects consist.
Matter is everything around you.
Matter is anything made of atoms and molecules.
Matter is anything that has mass (weight) and volume (takes up space).
Matter is everything and anything that is not energy, space, or time.
Matter makes up everything from the mountains to the oceans to the human body.
The things that are not matter are:
What is and is not matter
- Energy - Electromagnetism, light, heat
- Space - The area matter and energy exist in, like the area between two walls or between stars
States of matter: All the material on earth is in three states.
- Time - The progressive activities of things as they happen
A solid has a certain size and shape. The wood block is solid.
A solid has a fixed volume and shape, although it can be altered.
It has a size or volume, but it doesn't have a definite shape. It takes the shape of its container. Milk is liquid matter.
The molecules of a liquid are practically fixed in their volume and density, but not their shape. The molecules of a liquid can move around to fill a volume.
A gas is matter that has no shape or size of its own. Gases have no color. You can't see oxygen. It's invisible.
The least dense state, which has no fixed volume or shape, but can be changed in density (pressure) by changing its amount or its volume
By heating/condensation most of the matters changes its state.
The different types of matter can be distinguished through two components: composition and properties.
The composition of matter refers to the different components of matter along with their relative proportions.
These properties are generally grouped into two categories: Physical and Chemical.
Intensive: A physical property that will be the same regardless of the amount of matter.
- Density: Mass per volume.
- Color: The pigment or shade.
- Conductivity: ability of substance to conduct electricity.
- Malleability: if a substance can be flattened.
Extensive: A physical property that will change if the amount of matter changes
- Luster: how shiny the substance looks.
- Mass: how much matter is present in the sample
- Volume: How much space the sample takes up
- Length: How long the sample is
Change in which composition of matter remains same but its state changes
- Three main states of matter are: Solid, Liquid, Gas
- Solid is distinguished by a fixed structure. Its shape and volume do not change. In a solid, atoms are tightly packed together in a fixed arrangement.
- Liquid is distinguished by its malleable shape but constant volume.
- In liquid, atoms are close together but not in a fixed arrangement.
- Gas is made up of atoms that are separate. However, unlike solid & liquid, a gas has no fixed shape and volume
Any characteristic that gives a sample of matter the ability/inability to undergo a change that alters its composition. Example: Paper's ability to burn
Change in which one or more kinds of matter are transformed to new kinds of matter with altered compositions (Or Chemical Reaction).