visi jurusan kimia : institusi pendidikan dan pengembangan ilmu kimia yang bertumpu pada sumber daya...
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VISI JURUSAN KIMIA :
Institusi pendidikan dan pengembangan ilmu kimia yang bertumpu pada sumber daya lokal, memiliki nilai tambah dan
berwawasan lingkungan.
Materi dan sifat-sifatnya
Apakah kimia?
• Kimia adalah Ilmu yang mempelajari materi dan perubahannya
• Materi- Apapun yang menempati ruang dan memiliki massa.
• Perubahan Kimia- Perubahan yang menghasilkan materi berbeda/baru.
Apakah materi dan energi ada hubungannya
• Materi adalah apapun yang memiliki massa dan volume
• Energi merupakan materi yang bergerak
• 0 Kelvin dianggap suhu di mana materi tidak bergerak
• Maka suhu berhubungan dengan massa yang bergerak
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Di sekitar kita
• Apapun yang ada di ruangan,yang dapat dilihat, disentuh, dibau atau dirasakan….
• adalah materi.
Pada umumnya, materi sangat kecil dikenali sebagai atom
Setiap materi dapat dalam 3 keadaan:
• Padat, Solid
• Cair, Liquid
• Gas, Gas
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Atoms and Molecules
• Atoms are the tiny particles that make up all matter.
• In most substances, the atoms are joined together in units called molecules.The atoms are joined in
specific geometric arrangements.
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Structure Determines Properties• The atoms or molecules have different
structures in solids, liquids, and gases − leading to different properties.
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Matter: is it pure or impure
• Pure Substance = All samples are made of the same pieces in the same percentages. Salt
• Mixtures = Different samples may have the same pieces in different percentages. Salt water
Zat murniKomposisi tetap
Homogen
CampuranKomposisi bervariasi
Materi
Heterogen
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Mixtures
1. Made of multiple substances, but appears to be one substance.
2. All portions of a sample have the same composition and properties.
1. Made of multiple substances, whose presence can be seen.
2. Portions of a sample have different composition and properties.
Heterogeneous Homogeneous
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Matter Summary
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Setiap materi memiliki sifat,materi berbeda memiliki sifat berbeda
• Physical Properties are the characteristics of matter that can be changed without changing its composition.Characteristics that are directly observable.
• Chemical Properties are the characteristics that determine how the composition of matter changes as a result of contact with other matter or the influence of energy. Characteristics that describe the behavior of matter.
Chapter One 13
H2O Physical verses H2O Chemical
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Physical Properties
Melting Point Boiling Point
Electrical Conductivity
Thermal Conductivity
Magnetism
Malleability Ductility Specific Heat
Color Order Taste
Solid Liquid Gas
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Some Physical Properties of Iron• Iron is a silvery solid at room temperature with a metallic taste
and smooth texture.• Iron melts at 1538 °C and boils at 4428 °C.• Iron’s density is 7.87 g/cm3.• Iron can be magnetized.• Iron conducts electricity, but not as well as most other common
metals.• Iron’s ductility and thermal conductivity are about average for a
metal.• It requires 0.45 J of heat energy to raise the temperature of one
gram of iron by 1°C.
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Chemical Properties
Acidity Basicity
Inertness Explosiveness
Inflammable Flammable
Oxidizing Reducing
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Some Chemical Properties of Iron
• Iron is easily oxidized in moist air to form rust.
• When iron is added to hydrochloric acid, it produces a solution of ferric chloride and hydrogen gas.
• Iron is more reactive than silver, but less reactive than magnesium.
Quiz: is it a Physical or Chemical Property
• Salt is a white, granular solid = physical.• Salt melts at 801 °C = physical.• Salt is stable at room temperature, it does not decompose
= chemical.• 36 g of salt will dissolve in 100 g of water = physical.• When a clear, colorless solution of silver nitrate is added
to a salt solution, a white solid forms = chemical.
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Matter has Properties, Matter can also go through Changes
• Changes that alter the state or appearance of the matter without altering the composition are called physical changes.
• Changes that alter the composition of the matter are called chemical changes.
During the chemical change, the atoms that are present rearrange into new molecules, but all of the original atoms are still present.
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Is it a Physical or Chemical Change?• A physical change results in a different form of
the same substance.The kinds of molecules don’t change.
• A chemical change results in one or more completely new substances.Also called chemical reactions.
The new substances have different molecules than the original substances.
You will observe different physical properties because the new substances have their own physical properties.
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Phase Changes ArePhysical Changes
• Boiling = liquid to gas.• Melting = solid to liquid.• Subliming = solid to gas.• Freezing = liquid to solid.• Condensing = gas to liquid.• Deposition = gas to solid.• State changes require heating or cooling the substance.
Evaporation is not a simple phase change, it is a solution process.
• Evaporation of rubbing alcohol = physical.• Sugar turning black when heated = chemical.• An egg splitting open and spilling out =
physical.• Sugar fermenting into alcohol = chemical.• Bubbles escaping from soda = physical. • Bubbles that form when hydrogen peroxide is
mixed with blood = chemical.22
Quiz: is it a Physical or Chemical change
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Separation of Mixtures• Separate mixtures based on different
physical properties of the components.Physical change.
Centrifugation and
decanting
Density
EvaporationVolatility
ChromatographyAdherence to a surface
FiltrationState of matter (solid/liquid/gas)
DistillationBoiling point
TechniqueDifferent Physical Property
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Distillation: different boiling points
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Filtration: different solubility's
Summary• Moving Matter has Energy. Motion is
related to temperature. All energy formulas are relations between mass and temperature
• Matter has 3 states
• Matter has properties
• Matter can change
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States/Properties/Changeare all related to temperatureand how much you have
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Law of Conservation of Mass• Antoine Lavoisier
• “Matter is neither created nor destroyed in a chemical reaction.”
• The total amount of matter present before a chemical reaction is always the same as the total amount after.
• butane + oxygen carbon dioxide + water 58 grams + 208 grams 176 grams + 90 grams
266 grams = 266 grams
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Law of Conservation of Energy
• “Energy can neither be created nor destroyed.”
• The total amount of energy in the universe is constant. There is no process that can increase or decrease that amount.
• Note: neither Mass nor Energy are ever destroyed
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Energy• The Fundamental Principle of the Universe is
Energy• From the Greeks to Newton to Quantum
Mechanics Energy is known as the capacity to do work and is simply calculated by knowing the mass and velocity of a particle.
• The harder you swing an ax the faster you can fall a tree.
• Guess what happens when you walk into a wall .005 mph or 500 mph