16.1 – Classifying Matter Matter describes anything that has mass and

takes up space. Different kinds of matter have different characteristics.

Matter can be divided into two categories: mixtures and substances.

• Mixtures contain more than one kind of matter.

• Two types of mixtures: A homogeneous mixture is the same throughout. Ex: Dr. Pepper

• A heterogeneous mixture is one in which different samples are not made up of exactly the same proportions. Ex: Trail Mix

All mixtures, share one property: Can be separated into different types of matter by physical means (filtering or heating).

Substances cannot be separated into different kinds of matter by physical means. Elements and compounds are substances.

Elements are found on the periodic table. If it is not on the table then it is not an element. Ex: water is not but H and O are

Compounds are made of two or more elements that cannot be separated by physical means. Ex: Water(H20) and Salt(NaCl)

16.2- Measuring Matter• Measuring the volume of liquid matter is easy.

Simply pour it into a marked container such as a measuring cup, graduated cylinder, or beaker, and read the volume.

• Read the meniscus at the bottom of the curve.

To calculate the volume of solids, we use different formulas. See Pg. 272

Displacement is used to find the volume of an irregular shaped object.

A balance measures the mass of an object while a scale measures the gravitational force between an object and Earth.

Indirect measurement can also be used to measure very small and very large quantities.

Smallest possible particle of a compound that retains its properties is a molecule. Smallest possible particle of an element is called an atom.

Water is one of the most important substances. It covers more than 70% of the Earth’s surface. A water molecule contains 1 oxygen atom and 2 hydrogen atoms.

Must Draw

Temperature influences changes of state. Higher the temp, the faster the molecules move.

Temperature at which a solid is change to a liquid is its melting point. The temp at which it changed from liquid to gas is the boiling point.

Evaporation is the transformation from the liquid to gas. It is a cooling process.

The process of transforming from a gas to a liquid is condensation.

Sometimes a solid can change directly to a gas, this process is sublimation.

All substances can exist as a solid, liquid, or gas.

Solids -- definite shape and definite volume. Liquids -- definite volume but no definite

shape. Gases --no definite volume or no definite

shape.

Since molecules are always in motion, they vibrate differently in solids, liquids, and gases.

When a substance undergoes a change of state, only the movement of the molecules changes.

The number of molecules does not change, only the speed at which the molecules are vibrating changes.

The mass of the substance remains the same whether it is in the solid, liquid, or gas state.

The most common state of matter in the universe is a state rarely found on Earth: plasma. Matter enters the plasma state when it is heated to a high temp that some of the atoms begin to break apart. For most materials this requires temp of more than 10,000o.