Separating shows the different components and different properties of the mixtures. You need to think of a process that can separate between components with different properties.
http://sciencepark.etacude.com/projects/separations/separation1.php
This website lists and explains several basic techniques for separation of mixtures, such as filtration, evaporation, crystallization, distillation, and chromatography.
Monday, October 18, 2010
Thursday, October 14, 2010
October 13 2010 - Naming Acids
Today we went over naming acids.
Naming Acids
Acids = compound composed of hydrogen ions and a negatively charged ion are dissolved in water (aqueous(aq)).
Monday, October 11, 2010
October 7 2010 -- Ionic and Covalent Compounds
Today we reviewed the properties of ionic and covalent compounds.
Ionic compounds are compounds that are made of 2 or more oppositely charged particles. They are held together by electrostatic forces and electrons are transferred from metal elements to non-metal elements.
In covalent compounds, the electrons are shared between two non-metal elements.
Ionic compounds are compounds that are made of 2 or more oppositely charged particles. They are held together by electrostatic forces and electrons are transferred from metal elements to non-metal elements.
In covalent compounds, the electrons are shared between two non-metal elements.
Thursday, October 7, 2010
October 5 2010 - Lab
-We investigated the heating an
d cooling process for solid and liquid dodecanoic acid. So we'll be able to determine or compare the freezing and melting point.
-We heated and cooled the dodecanoic acid with a hot plate, beaker with water and tube clamps
-When the acid was freezing you can see the white crystals forming and it texture
-When the acid heats up, it is very noticeable, like melting ice but the acid is yellowish white
-We used a thermometer to measure the temperature s of the freezing and melting points of the acid
-We determined that the freezing point was 37'C and melting was 47'C
Monday, October 4, 2010
October 1 2010 -- Matter Is Made of Atoms
Atoms
• Atom – smallest possible piece of something
Elements
• Elements – pure substances that cannot be broken down
• Contains only one kind of atom
• Can exist as a solid, liquid, or gas
• Molecules – particles made of more than one atom
• Have different melting points and boiling points because they vary in mass and size
o The larger the particle, the higher the boiling point
Compounds
• Made by combining elements in definite properties
• Can also exist as solids, liquids, and gases
• Ions – particles that have an electrical charge
• Atom – smallest possible piece of something
Elements
• Elements – pure substances that cannot be broken down
• Contains only one kind of atom
• Can exist as a solid, liquid, or gas
• Molecules – particles made of more than one atom
• Have different melting points and boiling points because they vary in mass and size
o The larger the particle, the higher the boiling point
Compounds
• Made by combining elements in definite properties
• Can also exist as solids, liquids, and gases
• Ions – particles that have an electrical charge
October 1 2010 -- Matter in the Macroscopic World (text)
What You Know About Matter
• Water normally exists as a liquid that pours freely to fill any solid container, and will solidify if cooled, or evaporate if heated
• Properties such as color and taste of characteristics of matter
Purifying Matter
• Mixture – two (or more) kinds of matter that have separate identities
o Easily separated into component parts
o Said to be impure
o Mixtures like salt water or sugar water that look uniform throughout and do not scatter light are called solutions
o Separating solutions like salt water or sugar water by boiling them dry on the stove is called distillation
Characteristics of Pure Substances
• Pure substances have a constant boiling point
• Freezing point – the temperature at which a liquid solidifies
• Melting point – the temperature at which a solid liquefies
Chemical and Physical Changes
• Density – a property of matter that describes its mass per unit volume
• Chemical change – changes that produce a new kind of matter with different properties
• Decomposition – when one kind of matter breaks apart to create two or more kinds of matter
• Physical change – changes that are easily reversed to get the original material back again; do not appear to produce new kinds of matter
Compounds and Elements
• Electrolysis – involves passing an electric current through a substance to make it decompose into new kinds of matter
• Compounds – pure substances that can be decomposed into new kinds of matter
• Elements – elemental building blocks of all kinds of matter; cannot be decomposed
o 109 known elements
• Water normally exists as a liquid that pours freely to fill any solid container, and will solidify if cooled, or evaporate if heated
• Properties such as color and taste of characteristics of matter
Purifying Matter
• Mixture – two (or more) kinds of matter that have separate identities
o Easily separated into component parts
o Said to be impure
o Mixtures like salt water or sugar water that look uniform throughout and do not scatter light are called solutions
o Separating solutions like salt water or sugar water by boiling them dry on the stove is called distillation
Characteristics of Pure Substances
• Pure substances have a constant boiling point
• Freezing point – the temperature at which a liquid solidifies
• Melting point – the temperature at which a solid liquefies
Chemical and Physical Changes
• Density – a property of matter that describes its mass per unit volume
• Chemical change – changes that produce a new kind of matter with different properties
• Decomposition – when one kind of matter breaks apart to create two or more kinds of matter
• Physical change – changes that are easily reversed to get the original material back again; do not appear to produce new kinds of matter
Compounds and Elements
• Electrolysis – involves passing an electric current through a substance to make it decompose into new kinds of matter
• Compounds – pure substances that can be decomposed into new kinds of matter
• Elements – elemental building blocks of all kinds of matter; cannot be decomposed
o 109 known elements
Sunday, October 3, 2010
October 1 2010 -- New Laws and the Heating/Cooling Curve of a Pure Substance (notes)
On Friday, we started a new topic about matter and the heating/cooling curve of a pure substance.
Law of Definite Composition
Compounds will have a definite composition. For example, water (H2O) will be water anywhere (it always have 2 hydrogens and 1 oxygen).
Law of Multiple Proportions – when two or more compounds with different properties of the same elements can be made. For example, carbon dioxide (CO2) x 2 = dicarbon tetraoxide/oxalate (C2O4).
A : At this point, the pure substance is in the solid state, because the pure substance is below the melting point. The particles are packed together closely in an orderly manner. Particles can only vibrate at a fixed position and the forces between the particles are very strong.
A-B : When the pure substance is heated, the heat energy is converted to kinetic energy. The molecules vibrate faster in their fixed positions and the temperature increases when the kinetic energy increases.
B : The pure substance is still solid, but the melting stage has begun – the solid begins to change into a liquid. The temperature remains the same.
B-C : The pure substance exists in both solid and liquid states. The heat that is supplied to it is used to overcome the forces of attraction that holds the particles together because the temperature remains constant. This constant temperature is called the melting point. The latent heat of fusion is the heat energy absorbed to overcome the intermolecular forces.
C : The pure substance has completely melted, and the solid has turned to liquid.
C-D : The pure substance is in liquid state, and as the liquid is heated and the temperature is increased, the particles move faster because the kinetic energy is increasing.
D : The pure substance is still in liquid state, and the molecules have gained enough kinetic energy to overcome the forces of attraction between the particles. Some of the molecules begin to change into gas.
D-E : The pure substance is in both liquid and gaseous states. The temperature is unchanged, and the heat energy absorbed is used to overcome the molecular forces between the particles of the liquid rather than increase the temperature. This constant temperature is called the boiling point.
E : All of the pure substance liquid has turned into gas.
E-F : The gas particles continue to absorb more energy and move faster. The temperature increases as heating continues.
Law of Definite Composition
Compounds will have a definite composition. For example, water (H2O) will be water anywhere (it always have 2 hydrogens and 1 oxygen).
Law of Multiple Proportions – when two or more compounds with different properties of the same elements can be made. For example, carbon dioxide (CO2) x 2 = dicarbon tetraoxide/oxalate (C2O4).
A : At this point, the pure substance is in the solid state, because the pure substance is below the melting point. The particles are packed together closely in an orderly manner. Particles can only vibrate at a fixed position and the forces between the particles are very strong.
A-B : When the pure substance is heated, the heat energy is converted to kinetic energy. The molecules vibrate faster in their fixed positions and the temperature increases when the kinetic energy increases.
B : The pure substance is still solid, but the melting stage has begun – the solid begins to change into a liquid. The temperature remains the same.
B-C : The pure substance exists in both solid and liquid states. The heat that is supplied to it is used to overcome the forces of attraction that holds the particles together because the temperature remains constant. This constant temperature is called the melting point. The latent heat of fusion is the heat energy absorbed to overcome the intermolecular forces.
C : The pure substance has completely melted, and the solid has turned to liquid.
C-D : The pure substance is in liquid state, and as the liquid is heated and the temperature is increased, the particles move faster because the kinetic energy is increasing.
D : The pure substance is still in liquid state, and the molecules have gained enough kinetic energy to overcome the forces of attraction between the particles. Some of the molecules begin to change into gas.
D-E : The pure substance is in both liquid and gaseous states. The temperature is unchanged, and the heat energy absorbed is used to overcome the molecular forces between the particles of the liquid rather than increase the temperature. This constant temperature is called the boiling point.
E : All of the pure substance liquid has turned into gas.
E-F : The gas particles continue to absorb more energy and move faster. The temperature increases as heating continues.
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