Introduction to matter

What it mass Mass- the amount of matter that an object has Weight- the force of gravity on the mass of an object Is mass the same everywhere?

Matter What is matter? Matter is a term for the substance of which all physical objects are made. Matter is made up of very small particles called atoms.

Matter is found in three different phases Solid Liquid Gas

Liquid Gas Solid

Properties of a solid Solids- A substance in a solid phase is relatively rigid, has a definite volume and shape. The atoms or molecules that comprise a solid are packed close together and are not compressible.

A solids atoms do move. However, this movement is very small and very rapid, and cannot be observed under ordinary conditions

Properties of a liquid Liquids have a definite volume, but are able to change their shape by flowing. Liquids are similar to solids in that the particles touch. However the particles are able to move around. Since particles are able to touch the densities of liquid will be close to that of a solid.

Since the liquid molecules can move they will take the shape of their container.

Properties of a gas Gases have no definite volume or shape. If unconstrained gases will spread out indefinitely. If confined they will take the shape of their container. Each of the particles are well separated resulting in a very low density.

Density Density- is defined as its mass per unit volume. The formula for density is given as

Mass- The amount of matter and object has. It is often referred to the weight of an object. Often expressed by grams = g Volume- is how much three-dimensional space a substance or shape occupies or contains. Often expressed by mL or cm 3

Example problem A 43 gram block of wood has a volume of 30 cm 3 what is the density of the block?

If a block has the mass of 15 grams and a density of 2 grams/cm 3 what is its volume?