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in chemistry. Everything that we study consists of matter
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. Matter is something that occupies space and has a
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mess. Mass is defined as the amount of matter
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that it contains, and it is often measured in
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things like grams or kilograms. It is important to
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note that mass is not measured in pounds, which
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is a weight that is dependent on the gravitational pole
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of another mass. In nature. There are technically
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for states of matter, but in this course we
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will be focusing on three, which is the guest
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liquid and solid phases. So for the gas phase
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, these are made up of atoms or molecules that
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are not bound together, which move independently of each
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other in all directions in three dimensional space and are
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also shapeless, meaning that they will spread out to
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fill any container or space that they can occupy.
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Gasses are also compressible if they're subjected to changes in
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pressure or temperatures, so if you increase the pressure
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, you will compress the gas, and if you
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decrease the pressure, the gas will expand and these
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changes will also occur with changes in temperature and examples
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of gasses include things like oxygen, gas, hydrogen
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gas as well as carbon dioxide. So the next
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phase that we will be talking about is the liquid
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face. And for liquids, thes atoms or molecules
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can move freely around each other, but to is
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to a certain extent because they are loosely bound together
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. There are also amorphous, and we'll take the
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shape of the container that it is in. And
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they're not compressible under changes, impression or temperature and
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therefore have a fixed volume. And examples of thes
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include something like water that we're all very familiar with
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, as well as elemental mercury, which at room
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temperature is a liquid and it is often found in
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traditional thermometers. So the last phase that we will
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be talking about is the solid phase. And in
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the solid phase, atoms or molecules are bound together
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, resulting in a rigid structure. They don't move
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around each other, bubble, move in place or
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vibrate in place. And like liquids, they're not
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compressible on our changes in pressure and temperature, and
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therefore have a fixed volume as well. And examples
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of these include sodium chloride or more well known as
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table salt for the mineral highlight, and another example
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would be solid water which we call ice. So
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matter can exist and these three different states and can
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also undergo something called a phase change. Where matter
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changes from one state to another state via the making
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or breaking of inter molecular bonds, which are bonds
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between molecules and an example of this would be liquid
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water freezing into ice in the freezer section of a
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bridge. So in addition to face changes, matter
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can also physical and chemical properties. Physical properties can
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be further broken down into something called extensive and intensive
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properties. So first off examples of physical properties include
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things like math melting. Point minus is, um
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, etcetera, and these can be further categorized into
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extensive and intensive properties, so expensive properties are dependent
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on the amount of stuff the substance has. So
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things like mass and volume are expensive properties, because
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if you have more matter by virtue, you have
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more mass and more volume. Everything else on this
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list are intensive properties, which are independent of the
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amount of Seth the substance has. So regardless of
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whether you have something like 1 g of sugar or
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30 g of sugar, all of these will melt
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and boil at the same point. And in addition
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to physical properties, matter also has chemical properties,
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and examples of these include flammability and reactivity and reactivity
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is how matter can interact with other types of matter
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through intra molecular bonding or bonding between Adams.