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What is. Matter ?. Matter. Is anything that has mass and takes up space. Where: Space = the size or volume. Mass = the amount of matter. Can someone give me an example of matter?. If all of these are examples of matter then, why are they so different?. Matter.
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What is Matter ?
Matter Is anything that has mass and takes up space. Where: Space = the size or volume. Mass = the amount of matter. Can someone give me an example of matter? If all of these are examples of matter then, why are they so different?
Matter Matter is different because: • Matter is composed of atoms. • Not necessarily the same atoms. • Therefore one type of matter can be very different from another type.
Matter Can matter composed of the same exact atoms have different forms? YES ! These forms of matter are called “States of Matter”
Examples of the “States of Matter” Liquid Solid Gas Plasma
Gases • A gas is composed of atoms or molecules. 2. There are no attractive or repulsive forces between the particles. 3. These particles move rapidly in constant random motion and fill the container they are in. 4. When gas particles hit other objects they do not slow down (lose energy). This is called being “perfectly elastic”.
LIQUIDS • Particles of liquids do not move around as easily as gases. • They are stuck together (bound) by intermolecular forces. Intermolecular forces – the forces that hold molecules together. • They can still slide around each other and take the shape of their container.
Solids The atoms in a Solid are bound tightly together by intermolecular forces. The atoms hold their shape and have fixed volume. The atoms in a solid can vibrate but cannot change position.
So ............... The molecules or atoms of aGASare not bound to each other and are in constant motion. The molecules or atoms of aLIQUIDare loosely bound together and slide around each other. The molecules or atoms of a SOLID tightly bound together. They can vibrate but do not change position relative to each other.
By each letter, write one of the following: • Definite shape • Changeable shape • Definite volume • Changeable volume Solid Liquid Gas
Definite volume Definite shape Changeable shape Changeable volume
So what’s the deal with all of this movement? Why are all of these atoms and molecules moving around so much?
Kinetic Energy Kinetic Energy is the energy of motion You can also think of kinetic energy as: Heat Therefore, the more kinetic energy the higher the temperature!
Changing States What does it take to change state of matter? Adding heat! (endothermic) or Removing heat! (exothermic)
Ice (solid), when heated turns to… Water (liquid), when heated turns to…
Changing States Temperature Heat or Kinetic Energy
If you heat a solid it turns to a liquid. If you heat a liquid it turns to a gas. What happens when you heat a GAS?
Plasma The forth state of matter When a gas is heated to a VERY high temperature the result is a Plasma. Plasma is by far the most common form of matter. Plasma in the stars and in the space between them accounts for approximately 99% of all matter in the universe.
Can it get so cold that particles STOP moving? • Yes! • Absolute zero! • Absolute zero is the temperature at which there is NO KINETIC ENERGY Absolute Zero is Oo Kelvin or -273o Celsius or -460o Fahrenheit
Temperature • Degrees Celsius • Degrees Fahrenheit • Degrees Kelvin Scottish physicist William Thomson, knighted as Lord Kelvin, (1824-1907), devised his absolute temperature scale based on the Celsius scale. His work in the field of physics led him to devise the Kelvin scale, based on Celsius-sized degrees. His absolute scale began at absolute zero, -273°C.
How do all of these scales compare? Absolute Zero is: O degrees Kelvin -or- -273 degrees Celsius
Fifth State of Matter? Bose-Einstein Condensate Scientists used a laser and magnetic traps to create the BEC. The condensate is made of a tiny ball of rubidium atoms that are all stationary. The condensation occurs when individual atoms meld into a "superatom" behaving as a single atom at just a few hundred billionths of a degree above absolute zero. The physicists likened it to an ice crystal forming in cold water.
Element A material that is made of only one type of atom. It can not be broken down into simpler substances by chemical means.
Compound A substance that has two or more elements chemically combined. It can be broken down into simpler substances by chemical means. C8H10N4O2
Mixture A substance that has two or more elements or compounds that are mixed together but ARE NOT chemically combined.
Physical and Chemical Properties Physical Properties Shape Size Color Odor Boiling Point Melting Point Density Chemical Properties Flammability Heat of Combustion Reactivity pH
Physical and Chemical Change Physical Change Change in Shape Change in Size Change in State freezing Boiling It’s still the same stuff !!! Chemical Change Flammability Heat of Combustion Reactivity pH Now you have different stuff !!!
Conclusion The Temperature, of a substance is directly proportional to the amount of kinetic energy that substance holds.
Therefore, if you increase the temperature of a material you increase the movement of the atoms and molecules. If you increase the temperature (kinetic energy) enough will a solid turn to a liquid or a liquid turn to a gas?
What do the liquids need to escape? • Enough kinetic energy! • This allows them to overcome the intermolecular forces Intermolecular forces Liquids
Dynamic equilibrium – when the relative number of vapor and liquid particles is equal
Evaporation is a cooling process. Why? • As the warmer particles evaporate, the average temperature of the remaining (cooler) particles is lower Analogy: take out the fastest runner in your relay race, and your overall speed decreases
How do you make a liquid boil? 1. Heat it! – This gives gas particles enough energy to evaporate. Is there another way??? 2) Change external pressure – This way, liquid particles don’t need such a high vapor pressure to overcome atmospheric pressure.
If you have a liquid, say water, and you increase the temperature enough what happens? Boiling point • Temperature at which vapor pressure of a liquid equals the external pressure • Bubbles of vapor form
More about boiling • Liquid can overcome pressure from the atmosphere, it boils. • Normal boiling point – is the boiling point at 101 kPa or 1 atm of pressure
Amorphous Solids Randomly arranged atomic structure (glass)
Gas molecules inside a volume (e.g. a balloon) are constantly moving around freely. During this molecular motion they frequently collide with each other and with the surface of any enclosure there may be (in a small balloon that would be many thousands of billions of collisions each second). In the example of the balloon (above), there is not only gas inside the balloon (exerting pressure from the inside), but there is also gas (air) on the outside, exerting pressure onto the outside surface of the balloon.
Solids MOLECULAR • Lower melting point • Less Organized Structure
If hydrogen gas at 200K has four times the kinetic energy of another sample of gas, what is the new gas temperature? Can you tell me ??? 50 K
Heat not only will increase the evaporation rate of a liquid but it will also increase ….. Pressure • Caused by the collision of particles • In evaporation, particles hit the walls of the container to create vapor pressure • Vapor pressure – the pressure exerted by vaporized gas particles
Kinetic Energy What Is Kinetic Energy? • Kinetic energy is energy from movement When physicists talk about kinetic energy this is what they are talking about…. But chemists look at kinetic energy on an atomic level.
Solids Melting Point Changing a solid to a liquid by adding enough energy (heat) to break intra-molecular forces.
Solids Sublimation Changing of a solid directly to a gas by adding enough heat energy to overcome intra-molecular forces.
What is this process called were molecules leave the liquid state and turn into a gas? Evaporation Liquid Moleculesare sticky, so they tend to hold together to form a liquid. If the water is given some energy, some of the molecules near the surface can escape into the air. They form a gas (also known as water vapor).
What speeds up evaporation? • Increased temperature! • This gives more particles enough kinetic energy to escape!!
Density is a characteristic of matter. • This means that the density of an object can help you determine what material the object is made from. • Density is calculated with the following equation: Density