Basic Chemisry

States of Matter

• Matter is everything around you. Matter has a mass. Atoms and molecules are all composed of matter. Matter is anything that takes space. There are 5 states of matter, are also called Phases. Five stages of matter are:
• 1. Solid
• 2. Liquid
• 3. Gas
• 4. Plasma,invented by William Crookes in 1879
• 5. Bose-Einstein condensate, the scientists worked on this Phase got a Nobel Prize in 1995.
• All 5 states of matter has different physical properties.
• Physical State vs Chemical State:
• 1. Physical State: Molecules can move from one physical state to another without impacting the Chemical composition. For eg., O2 gas can have a same chemical properties as of Liquid Oxygen. Matter can change its state to Solid, Liquid or Gas without changing the Chemical properties.
• 2. Chemical State: In this state, bonds of the molecules can be created or destroyed. For eg., Water ( H2O) can be chemically change by adding second atom of Oxygen to make it H2O2.
• Changes in Physical State depends upon the environment conditions as well. There may be some chemical changes occur under environmental conditions such as Sun, molecules can be destroyed. Elements and compounds can change a physical state by Temperature, energy etc.
• http://www.chem4kids.com/files/matter_intro.html

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• Examples of Matter:
• When we heat up Water (H2O), with the increase of the temperature the molecules of water gets excited and bounce even more. Continuing heating up the water will evaporate the molecules and takes a form of Gas.
• Similarly, When you cook a food, the molecules inside the food gets heated up and takes a form of gas, so that we can smell the food while cooking.
• All matter can move from one state to another. it may require extreme temp or extreme pressure to change the state. For example, Oxygen (O2) can be solidify by cooling down to -218.8 Degree Celsius with standard pressure. However it will also freeze at warmer temperature when pressure is increased.
• 

Points of Change

• Phase changes happens when phase reaches a certain point.
• Melting Point and Freezing point are used to measure the temperature increase or decrease for a liquid to change it state to solid or vice versa. Sometimes increasing a pressure will also increase the freezing point of the substance. It is easier to get the things in solid state under high pressure.
• Usually, molecules are closer together in solids. But Water is special at many level in terms of science. The molecules has more spacing between them when water if frozen (Ice). This is because molecules in water have a special arrangements where as generally the molecules are all loosey-goosey in liquids. Same number of molecules will take more space when they are arranged than the freely moving molecules.
• CHEMISTRY TERM PHASE CHANGEFusion/Melting
• Freezing
• Vaporization/Boiling
• Condensation
• Sublimation
• Deposition
• Solid to Liquid
• Liquid to Solid
• Liquid to Gas
• Gas to Liquid
• Solid to Gas
• Gas to Solid
• Note: Atoms in a liquid have more energy than atoms in a solid.
• When solid reached its melting point then it becomes liquid. Solid has to little over 0 degrees Celsius to become liquid (melt). Salt, sugar

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• and rock has a high melting point because they are not liquid even when temperature above 0 degree Celsius. (Copied: If you were salt, sugar, or rock, your melting point is higher than that of water. How do you know that fact? If their melting points were lower, they would also be liquids when the temperature is above zero degrees Celsius. If their melting points were lower, they would also be liquids when the temperature is above zero degrees Celsius. )
• The reverse of melting process is freezing. Water becomes solid ice when molecules loose energy.
• Sublimation - Solid to Gas; Dry Ice is a solid Carbon dioxide which turns from solid to gas directly. Another example is Coal turns to Gas from solid under very high temperatures.
• Deposition- Gas to Solid; In winter, vapors from air becomes frost crystals (ice) over plants.
• Vaporization- When molecules in a liquid gets enough energy and starts vibrating. At some point, the molecules get enough energy and escapes the liquid limitations and becomes gas. It is also called a boiling point.
• Condensation: It is opposite to vaporization. When molecules loose some energy and transfer to the colder environment when the temperature decreases, gas turns into liquid.
• Gas to Plasma: When you group the electrons and protons equally, so that the gas has a neutral charge. This makes all the atoms equally charged and constitute a plasma ball. Neutral happens when positive atoms cancels out the negative charge atoms. Plasma can be made when a lot of energy pushed into gas molecule.
• Plasma to Gas: Taking off (pulling-off) the energy switch, the molecules will become unstable by having not equal amount of +ve and -ve charged atoms.
• Physical Change: It is not a chemical change. When you press a can of soda, its shape changed but not phase change (Chemical or state from solid to liquid or gas). There was no energy passed, only force. When you melt an ice cube, then it changes the physical state from solid to liquid as the energy added.
• Molecular Change: It is a chemical change. These changes occur when the chemical composition has been changed. These changes may or may not impact the physical state. Such as H2O to H2O2 changes the molecular composition but the physical state is still liquid. Iron (Fe)

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• rust is a chemical change when Oxygen reacts with metal. As the molecules change their state as the iron oxidized and becomes Iron Oxide (Fe2O3).
• Isomers: When atoms are bonded in a different orders but the total number of atoms are same is called Isomers. For example Glucose, Fructose and galactose all have 6 carbon, 12 Hydrogen and 6 Oxygen atoms but all have different shapes and other properties. Body understand glucose only, so if person eats galactose, the body converts into glucose first.

Solid Basics

• Solids holds their shape because the molecules are tightly packed. Even if you powered a rock and is visible to see under the microscope, it is still a solid.
• Solid Mixture: Mixture more than one solids. Concrete is the example.
• Granite: It is called Heterogeneous mixtures. Consist of more than one mixture present in uneven form.
• Crystals: When molecules are arranged in a specific manner, forms a crystals. All substances cannot form the crystals. Crystal is the purest form of the substance. In a figure, you see a Lattice Crystal when atoms are formed in that shape. Diamond is another example of Crystal.
• Allotropes: When two atoms in a same material has a different carbon structures.
• 

Liquids

• If a different types of molecules dissolved in a liquid, then it is called solution.
• Honey is a solution of water, sugar and other molecules.
• The surface of the liquid is always Flat because of the gravity pulling the molecules.
• Liquids are difficult to compress because the molecules are closer together already.
• Applications: Compressed Oil is used in automobile shocks to reduce the stress on the automobile structure acts as dampening device.
• Solids are most harder to compress, then Liquids takes second place and Gas are the easily to compress. For example, In Scuba Tanks, gases are compressed.
• Inter Molecular Forces can be found in all substances. Molecules stick together because of the forces. Solid substances have molecules that are hard to separate, gas has the most freely moving molecules. Water molecules has the cohesive properties that is why they stick together. For example, if you see a drop on the water faucet, it do not drop until the external force push the drop or the weight of the water increases.
• Evaporation: Liquid to Gas
• When liquid molecules gain enough energy and escape the to the environment in a form of gas, then it is called evaporation. The energy is to applied and molecules starts vibrating and escapes the liquid when enough temperature is supplied to liquid. Evaporation is about the energy increase in individual molecules not the average energy in the system. Evaporation can occur when the average energy is low in the system.
• At 1 atmospheric Pressure= Boiling Point is 100 Degree Celsius. Atmospheric Pressure is low in Hilly areas(Pressure with Height: pressure decreases with increasing altitude. The pressure at any level in theatmosphere may be interpreted as the total weight of the air above a unit area at any elevation. At higherelevations, there are fewer air molecules above a given surface than a similar surface at lower levels.)
• Boiling Point will increase with increasing Pressure.
• https://www.youtube.com/watch?v=1kHdqxSrTzA
• Evaporation can happen when temperature is cold or warm but it happen more often when temperature is warmer. When matter has higher temperature, the molecules have the higher energy as well.

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