Unit One and Two Describing Matter
What is chemistry? The study of matter and the changes it undergoes.
What is matter? Anything that has mass and takes up space.
What are examples of matter? Almost everything, air, books, you, glass
What is not matter? Light, sound, heat, electricity, time, thoughts,
How can we describe matter? Either Chemically or Physically
What is a physical property? A property that describes how the matter looks Think describing words
What are some examples of physical properties? Color, smell, shape, texture, temperature
What are some other physical properties? Solubility, dissolving, conductivity,
What is conductivity? When a metal can conduct heat and electricity.
What is solubility? The same as dissolving, except it can be any state of matter. Dissolving is solids into a liquid
What is a chemical property? The way a substance can react with other substances to form new “stuff”
What are some examples of chemical properties? Can rust, reactive, combustible, flammable, non-reactive
So what does this really mean? It is how matter can change
What do chemical properties have to do with? Reactivity
What is reactivity? The ability to combine chemically with another substance
SORT IT OUT! With your partner, look at the sheet given. In your notebook, sort the words into three columns: 1. Chemical property 2. Physical property 3. We are not sure
When matter changes, what is it called? Either a chemical or physical change.
What is a physical change? Actually changing the way the matter is shaped or looks
What are some examples of physical changes? Cutting, grinding, dissolving, phase changes
What is a chemical change? When matter changes how it looks New substances are formed
What are some examples of chemical changes? Burning, rotting, rusting
When something changes chemically what is the end result? A completely new substance.
Sort it out! With your partner, Sort the cards into two piles. In your notebook, sort the words into two columns: 1. Chemical change 2. Physical change
What are the three states of matter? Solids, liquids and gases
What are the properties of solids? Particles are tightly packed, don’t move freely Lowest kinetic energy Definite shape and volume
What are the properties of liquids? Particles are close together, but can move past one another. Take shape of container. Definite volume, not definite shape
What are the properties of gases? Do not touch one another. Spread apart. Take shape of container Highest kinetic energy Not definite shape, not definite volume
Please refresh me on the phase changes MeltingFreezing EvaporationCondensation SublimationDeposition
In your notebooks, draw this: LIQUID SOLID GAS
How else can we classify matter? Either as a pure substance or a mixture
What is a pure substance? Something that you can not break down any further by physical changes.
What are the two types of pure substances? Elements and Compounds
What is an element? A substance that can not be broken down into simpler substances.
What happens when elements combine chemically? A compound is formed
How do you break apart a compound? Only by undergoing a chemical change.
What is an example of a compound? H 2 O (water), O 2 (oxygen gas), or Fe 2 O 3 (rust)
A mixture What is it called when 2 or more pure substances combine?
Can mixtures be separated? Yes, some are just harder to separate than others.
What are the 2 different kinds of mixtures? Homogeneous and heterogeneous mixtures
What is a heterogeneous mixture? A mixture with noticeably different parts.
What happens if a heterogeneous mixture sits? It will separate
What is an example of a heterogeneous mixture? Concrete, ranch dressing, a cow, chunky applesauce
Can you always just see the chunks in heterogeneous mixtures? No, some say shake well.
If something says shake well, what is it? A heterogeneous mixture with tiny chunks that will fall out of solution.
What is a homogeneous mixture? A mixture where you cannot see the different parts. Also called solutions
What happens if a homogeneous mixture sits? It stays mixed
What is an example of a homogeneous mixture? Marker ink, salt water, air, tea
How can you separate mixtures? Filtration Chromatography Decanting Evaporation Magnetic Attraction Distillation
What is filtration? Using a filter to separate solids from a liquid.
What is chromatography? Separating liquids on a piece of paper based on their mass. (Used for liquids that are mixed together that are different colors)
What is decanting? Pouring off a liquid from a solid particle that separates by gravity.
What is evaporation? Heating a liquid mixture, leaving behind a solid particle in the container. (Used for a solid dissolved into a liquid)
What is magnetic attraction? Using a magnet to remove one part of a mixture
What is distillation? Using the boiling points of two different liquids mixed together. (Used for 2 liquids mixed together that are the same color)