Applied Chemistry

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Definition: The capacity to do work or produce heat .
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Common unit: calorie abbreviated cal
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SI unit: Joule abbreviated J

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Radiant Energy is energy transferred through waves without matter .
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Ex. Sunlight
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Kinetic Energy is energy of motion .
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Walking, Running, Water flowing
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Potential Energy is energy of position or stored energy .
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Ball at the top of a hill, battery

Potential and Kinetic Energy

Forms of Energy
Mechanical, Heat, Chemical, Electrical,
Radiant, Sound, Nuclear

Law of Conservation of Energy
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Energy is neither created nor destroyed .
Energy can change from one form to another.

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Definition: anything that has mass and volume .
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States of matter:
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Solid
Liquid
Gas
Plasma l s g
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Name Shape
Definite
Volume
Definite
Density
Definite
Solid
Indefinite Definite Definite
Liquid
Indefinite Indefinite Indefinite
Gas
Plasma
Indefinite Indefinite Indefinite

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Change is state is also known as a phase change.
Temperature vs. Heat Animation

Solid
Liquid condensing evaporating
Gas

Properties or Characteristics of Matter
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A physical property is a property observed or measured without changing the material.
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Example: color, density, shape, melting point, boiling point
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A chemical property is a property that refers to the ability of a material to undergo a change that alters its structure.
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Examples: flammability, light sensitivity

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All changes involve a change in energy .
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Physical changes: Do NOT change the identity of a substance.
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Ex) size, shape, state, and dissolving
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Chemical changes: Do change the identity of a substance.
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Ex) burning, digesting food, rusting

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Change in color
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Formation of a precipitate (cloudiness; solid formed from 2 solutions)
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Production of a gas (bubbles; fizzing)
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Increase or decrease in temperature
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Change or production of an odor

o Chemical Equation – a shorthand way to write a o Starting materials are called reactants o Newly formed materials are called products o Reactants yields
Iron + Oxygen products
Rust

Law of Conservation of Matter
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Matter is neither created nor destroyed .
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Shown by the French chemist
Antoine Lavoisier in the 1700s. He is known as the Father of Chemistry .
mass of reactants = mass of products

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Contain only 1 type of atom .
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Cannot be broken down by ordinary means.
(physical or chemical)
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Ancient Greeks believed there were only 4 elements. ( earth, air, fire, and water )
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92 naturally occurring elements. Others are short-lived, man-made elements.

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A symbol is a shorthand way of writing the name of an element.
represents 1 atom of an element
Consists of 1 or 2 letters.
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1 st letter is ALWAYS capitalized.
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Subsequent letter is lower case.
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3-letter symbols are temporary designations assigned by IUPAC.

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Using your periodic table, find the symbols for the following elements:
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Hydrogen
H
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Helium
Carbon
Chlorine
He
C
Cl
The number of elements as a solid, liquid, or gas at room temperature
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2 liquids
11 gases
Others are solids

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Contain 2 or more different elements that are chemically combined.
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Can be broken down by chemical processes, such as heat and electricity.
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Smallest part of a compound is a molecule .

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A formula is a shorthand way of writing the name of a compound. It shows…
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Which elements are present
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The ratio of the elements present.

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H
2
O: the 2 is called a subscript that tells you that 2 atoms of hydrogen combine with 1 atom of oxygen to form 1 molecule of water.
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3H
2
O is read as 3 molecules of water.
The 3 is called the coefficient . There are 6 hydrogen atoms and 3 oxygen atoms

Identify the following substances as elements or compounds.
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Co Element
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CS
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CO
Compound
Compound
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Mg Element
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Note: If two capital letters are present, it is a compound.

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Step 1: List all elements present
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Step 2: Identify the coefficient
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Step 3: Count the number of atoms of each element in the compound.
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Step 4: Multiply the coefficient by the subscript
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Step 5: Add up all the atoms

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2
4
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2
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2
3
3

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Mixtures contain elements or compounds that are mixed together but not chemically joined.
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Types of Mixtures
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Homogeneous Mixture or Solution
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Heterogeneous Mixture or Mechanical Mixture

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Uniform throughout
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Not visibly different
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Examples:
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Gasoline
Food coloring
14 caret gold
Air
Brass lemonade

Brass is an alloy of copper and zinc.
Steel is an alloy of carbon and iron.
Bronze is an alloy of copper and tin.

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Not uniform throughout
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Visibly different
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Examples:
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Oil & vinegar
Salad
Concrete
Soup
Sand and water

Homogeneous vs. Heterogeneous
Mixtures

Separation of Heterogeneous
Mixtures: Filtration
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Separate suspended particles from a clear liquid by pouring through a screen , filter , or porous substance .
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Filtrate: the liquid that passes through the filter
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Residue: the solid left on the filter
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Examples: car filter, pool filter

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Separation of Heterogeneous
Mixtures: Magnetic Method
& Decanting
Magnetic Method
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Separate magnetic substances from nonmagnetic substances.
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Examples: iron filings and sulfur recycling center
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Decanting
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Separate liquids due to a difference in density
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Example: oil from water

Heterogeneous liquids can be decanted.

Separation of Homogeneous
Mixtures: Chromotography
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Separate pigments of ink using strips of paper.
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Remember Pete Cheat Lab
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Examples: dyes and chlorophyll

Separation of Homogeneous
Mixtures: Distillation
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Separate solution by a difference in boiling point . The liquids will evaporate and then condense back to a liquid.
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Ex. Salt water, crude oil
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Distillation Demo
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A Closer Look at Distillation

Separation of Homogeneous
Mixtures: Crystallization
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Separate a solution by evaporating the liquid and the solid will recrystallize .
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Examples: rock candy, salt water