WHAT IS CHEMISTRY?

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What Our Universe is Made Of

OUR UNIVERSE

• Our Universe is made basically out of a few parts.

• These parts make up everything we currently know in the entire Universe; from stars, to light, to people, to some things we have never really seen with our naked eyes.

PARTS OF OUR UNIVERSE

• We currently believe there are 4 components of the universe.

• Matter

• Energy

• Dark Matter

• Dark Energy

MATTER

• Matter is anything that has mass and takes up space

• This could also be described as anything that has mass and volume

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MATTER

• Matter is made of atoms

• Atoms are the smallest units of matter that can chemically react

• Almost everything that you see in your daily life is made of matter

STATES OF MATTER

• Matter comes in 3 common states

• Solid

• Liquid

• Gas

SOLIDS

• Solids hold their shape and are rigid in their structure

• Solids do not flow

• Solids have a definite volume and a definite shape

• Their atoms are packed closely and can only vibrate

LIQUIDS• Liquids are partially rigid

• The atoms touch but are able to move past each other

• Liquids are hard to compress

• They have a definite volume

• Atoms can vibrate, rotate, and move

GASES• Gases are not rigid

• Gases have HUGE spaces in between atoms

• Gases are easily compacted

• Gases have no definite volume or shape

• Gases can fill whatever container no matter what shape or size the container is

CHECKPOINT1. Nitrogen is at 25°C. It is contained within a sealed glass jar. The nitrogen is then

compressed into a much smaller container. How would you classify Nitrogen?

2. Jell-O is sitting in the fridge. It cannot be packed any smaller than the size that it is. It can jiggle but stays in the shape of a rectangle. How would you classify Jell-O?

3. Extra gravy is stored in the fridge in a rounded bowl. I takes up a definite amount of space. John dumps the gravy on a plate and it stays in the shape of bowl at first. After about a half hour, it slowly begins to lose its shape and spread across the plate. How would you classify cold gravy?

4. A LCD TV contains Liquid Crystals. These are molecules (atoms hooked together) that flow, but at a microscopic level, they hold their shape. They fill their container, but they retain a somewhat definite shape. The molecules can rotate, but they all rotate at the same time. How would you classify Liquid Crystals?

CHANGING THE STATES OF MATTER• You can change matter from one state

into another.

• Solid Liquid = Melting

• Liquid Solid = Freezing

• Liquid Gas = Evaporating

• Gas Liquid = Condensing

• Solid Gas = Subliming

• Gas Solid = Depositing

ENERGY

• Energy is anything that can exert a force on another object

• Energy does not have mass or volume

• Examples of energy are heat, light, X-rays, gamma rays, electricity, sound, etc. All of these things can exert a force but don’t take up space or have any mass.

MATTER AND ENERGY• Matter and energy are the only

things that we deal with in our daily lives

• They are the only things we have on Earth

• However, they are not the only things in the Universe

• We believe that mass and energy may only make up 5% of all ‘stuff’ in the Universe

DARK MATTER• Dark Matter is known to take up about 25% of the Universe

• It does not absorb light or reflect light so it can’t be seen. This is why it is ‘dark’

• It is known to be there because we cannot see it but it has gravity. It is actually pulling stuff toward it but we can’t see ‘it’

• However, we still don’t know what dark matter ‘is’

DARK ENERGY• It is thought that Dark Energy makes up

about 70% of the known Universe

• Very little is known about Dark Energy

• We think that it exerts a force that is causing the entire Universe to expand

• We know it likely exists because of changes in the colours of light as they pass through certain areas in space. This is a complicated topic but is related to the Doppler Effect (the reason sounds change as they get closer or farther away from you)

OUR UNIVERSE• This means that about 95% of the Universe is stuff that we have never seen

• All of your daily encounters are will stuff that only makes up 5% of everything that we know exists.

• Why is that important?

• There is an incredible amount of

discovery left to be had in the Universe.

There is still SO MUCH that we do not

know yet.

CHEMISTRY

• Since we are still learning what dark matter and dark energy are, we will only be dealing with matter and energy in this class

• Chemistry is the study of matter and how it changes

• This means we need to learn a little more about matter

MORE ABOUT MATTER

• Since matter is anything that has mass and takes up space, there are lots of different types of matter

• We have invented some different classifications for different types of matter

CLASSIFICATIONS OF MATTER

• Matter is usually put into 2 broad classifications:

• Pure Substances

• Mixtures

PURE SUBSTANCES• Pure substances are made of only one type

of particle

• They might be made of atoms or molecules

• Molecules are 2 or more atoms hooked (usually called bonded) together

• Each pure substance has its own unique properties

• Examples of pure substances would be sugar, oxygen, silica, manganese oxide, hydrogen peroxide, water, etc.

PURE SUBSTANCES• There are 2 types of pure substances

• Elements

• A pure substance that is made of only 1 type of atom. They cannot be broken down into simpler substances by chemical reactions

• All elements are listed on the periodic table

• Examples include oxygen, hydrogen, chlorine

• Compounds

• Made of 2 or more elements bonded together

• Compounds are chemically combined

• Examples include water (H2O) or calcium carbonate (CaCO3)

EXAMPLES• Sodium Chloride (salt) is made out

of sodium atoms connected to chlorine atoms. This makes it a Compound.

• Aluminum is made of only one type of atom, Aluminum atoms. Copper is made of only copper atoms. This makes them pure elements.

MIXTURES

• As well as pure substances, matter is also found in mixtures

• Mixtures are 2 or more types of pure substances

• Mixtures are not chemically bonded (hooked together) like a compound is

MIXTURES

• There are 2 types of mixtures

• Heterogeneous Mixtures

• Homogeneous Mixtures

HETEROGENEOUS MIXTURES• The 1st type of mixture is a heterogeneous mixture

• Heterogeneous Mixtures

• ‘Hetero’ means different

• A Heterogeneous mixture is a mixture in which you can see the different parts

• Examples would include salad dressings or chocolate chip cookies

HETEROGENEOUS MIXTURES

• There are 2 types of heterogeneous mixtures

• Mechanical Mixtures

• A mechanical mixture is when different substances that make up the mixtures are visible to the naked eye

• This would be things such as chocolate chip cookies or a bag of trail mix

HETEROGENEOUS MIXTURES• The 2nd type of heterogeneous mixture is a

suspension

• Suspensions are when large particles are suspended inside of another creating a cloudy mixture

• You can see the parts of a suspension with the naked eye

• An example of a suspension is a salad dressing. The spices and herbs are suspended in oil and vinegar.

HOMOGENEOUS MIXTURES

• The 2nd type of mixture is a homogeneous mixture

• Homogeneous

• ‘Homo’ means same

• A Homogeneous mixture is a mixture of 2 or more substances that look the same

• The parts are not distinguishable

• Examples would be peanut butter or Kool-aid

HOMOGENEOUS MIXTURES• One specific type of mixture is a

homogeneous mixture is a solution

• A solution is when one substance is dissolved in another.

• The different parts of a solution are not individually visual

• Solutions have to be clear but can be coloured

HOMOGENEOUS MIXTURES

• Another type of homogeneous mixture is a colloid

• Colloids look like one substance, but they are cloudy

• Examples of colloids are mayonnaise and milk

CHECKPOINT1. Classify this substance:

2. Classify this substance:

3. Classify this substance:

4. Classify this substance: