A. Major Points and Concepts
* Background
* Since ancient times, humans have used chemical changes to their advantages.
* application was before 1000 BC, examples are ore process to get purer metals and embalming fluids.
* Early Ideas of Matter
* Greeks- first people to try to explain why chemical changes occur in 400 BC.
* believed all matter was made up of fire, Earth, water, and air.
* Alchemy
* The next 2,000 years of chemical history was dominated by alchemy.
* Alchemy is a precursor of chemistry and speculative philosophy practiced in the Middle Ages and the Renaissance.
* Alchemy's major focuses were discovering methods for transmuting baser metals into gold and finding a universal solvent and an elixir of life.
* Alchemy can be traced back to Ancient Egyptian and Ancient Chinese.
* Robert Boyle
* developed idea of the element
* substance was an element useless it could be broken down into 2 or more simpler substances
* example would be air could not be an element because it could be broken down into simpler parts
* flaws were he held to idea that metals were not elements because he believed metals could change due to alchemy
* Element
* Scientists found matter can be broken down chemically into abut 100 different elements
* 116 elements have been discovered but 88 elements are natural
* Earth
* the first six main elements are oxygen, silicon, aluminum, iron, calcium, sodium
* Elements and the Body
* We are composed of elements, 25 elements are needed to live.
* 6 main elements are oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus
* Symbols for Elements
* name of chemical elements come from many sources
* many element names derived from Greek and Latin words that describe some property of the element
* Names of Elements
* many names come from descriptions of elements
* other names for locations of discovery or famous scientists
* Element and Element Symbol
* first letter of element symbol will be capitalized and second is not
* sometimes, second letter used in abbreviation is not first two letters in name
* symbols for some elements based on original Latin or Greek name
* Dalton's Atomic Theory
* most natural materials are mixtures of pure substances
* pure substances are elements or compounds
* law of constant composition- given compound will always contain same proportion
* John Dalton
* english scientist/teacher developed Atopic Theory
* elements are made of tiny particles called atoms
* all atoms of a given element are identical
* atoms of a given element are different from those any other element
* atoms of one element can combine with atoms of other elements to form a compound
* a given compound always has the same relative number types of atoms
* chemical reaction simply changes the way atoms are grouped together
* atoms are not created or destroyed in a chemical reaction
* Formulas of Compounds
* compound is distinct pure substance composed of atoms of two or more elements and contain exactly the same relative masses of those elements
* Rules for Writing Formulas
* each atom present is represented by element symbol
* number of each type of atom indicated by superscript written to right of element symbol
* when only one atom of a given type is present, superscript 1 is not written
* Structure of the Atoms
* Dalton's (1808) theory provided convincing explanation for composition of compounds that it was generally accepted
* people believed that atoms existed, did not have understanding of structure of atoms
* Plum Pudding Models
* J.J. Thomson (1890) atoms of any element can be made to emit tiny negative particles
* believed that is there is a negative there must be a positive to balance it out
* believed there was positive charge cloud with electron scattered to balance charge
* New Atomic Models
* Rutherford discovered when you hit an atom with a particle, there was a deflection
* suggested there was some sort of core to the atom
* if there was no core then particle will go straight through
* Parts of the Atom
* three parts- proton+, neutron, and proton
* electron has relative mass of 1 and charge of -1
* protons has relative mass of 1836 and charge of +1
* neuron has relative mass of 1839 and charge of 0
* Atomic Number
* atoms classified by atomic number (number of protons in nucleus)
* Isotope
* atoms of the same element having different numbers of neurons
* Mass Number
* approximately equal to number of protons plus number of neutrons
* Isotopes of Carbon with Atomic Mass
* carbon 12 has 6 protons and 6 neutrons
* carbon 13 has 6 protons and 7 neutrons
* carbon 14 has 6 protons and 8 neutrons
* protons stay the same and neutrons go up to meet number
* Mass Number and Atomic Number
* mass number of element is = to number of protons + number of neutrons
* ex. oxygen has 8 protons and 8 neurons, mass number is 16
* Periodic Tables
* atomic number, above chemical symbol, equal to the number of protons in nucleus
* number below is atomic mass
* Metals
* physical properties-
* efficient conduction of heat and electricity
* malleability (flatten into sheets)
* ductility (pulled to form a wire)
* lustrous (shiny) appearance
* Nonmetals
* lacks properties of metals
* nonmetal elements can be found in gas, liquid, and solid
* Ions
* electrically neutral atom, number of negatively charged electrons = number of positively charged protons
* when number of electrons in an atom differs from number of proton, atom is not longer neutral and has net charge
* atom with net charge is an ion
* States of Elements
* most elements reactive and combine to form new compounds
* some elements not reactive and can be found in pure elemental states
* nobel is term that is given to elements that have low reactivity
* nobel metals are gold, silver, and platinum
* nobel gases are all elements in group 8
* Diatomic Molecules
* some elements combine to themselves to form a molecule
* most molecules are gases at room temperature
* Allotropes
* non metals solids more varied than metals
* different forms of a given element
* Ions
* atoms that either gain or loose one or more electrons to form changed atoms
* cation is atoms that have lost one or more electrons forming a positive ion
* anion is atoms that gain one or more electrons to form negative ion
* Naming anion
* any element that becomes negative, dropping ine ending and adding ide to end
* Ionic Compounds
* both cation and anion must be present
* net charge of compound must be zero
* Since ancient times, humans have used chemical changes to their advantages.
* application was before 1000 BC, examples are ore process to get purer metals and embalming fluids.
* Early Ideas of Matter
* Greeks- first people to try to explain why chemical changes occur in 400 BC.
* believed all matter was made up of fire, Earth, water, and air.
* Alchemy
* The next 2,000 years of chemical history was dominated by alchemy.
* Alchemy is a precursor of chemistry and speculative philosophy practiced in the Middle Ages and the Renaissance.
* Alchemy's major focuses were discovering methods for transmuting baser metals into gold and finding a universal solvent and an elixir of life.
* Alchemy can be traced back to Ancient Egyptian and Ancient Chinese.
* Robert Boyle
* developed idea of the element
* substance was an element useless it could be broken down into 2 or more simpler substances
* example would be air could not be an element because it could be broken down into simpler parts
* flaws were he held to idea that metals were not elements because he believed metals could change due to alchemy
* Element
* Scientists found matter can be broken down chemically into abut 100 different elements
* 116 elements have been discovered but 88 elements are natural
* Earth
* the first six main elements are oxygen, silicon, aluminum, iron, calcium, sodium
* Elements and the Body
* We are composed of elements, 25 elements are needed to live.
* 6 main elements are oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus
* Symbols for Elements
* name of chemical elements come from many sources
* many element names derived from Greek and Latin words that describe some property of the element
* Names of Elements
* many names come from descriptions of elements
* other names for locations of discovery or famous scientists
* Element and Element Symbol
* first letter of element symbol will be capitalized and second is not
* sometimes, second letter used in abbreviation is not first two letters in name
* symbols for some elements based on original Latin or Greek name
* Dalton's Atomic Theory
* most natural materials are mixtures of pure substances
* pure substances are elements or compounds
* law of constant composition- given compound will always contain same proportion
* John Dalton
* english scientist/teacher developed Atopic Theory
* elements are made of tiny particles called atoms
* all atoms of a given element are identical
* atoms of a given element are different from those any other element
* atoms of one element can combine with atoms of other elements to form a compound
* a given compound always has the same relative number types of atoms
* chemical reaction simply changes the way atoms are grouped together
* atoms are not created or destroyed in a chemical reaction
* Formulas of Compounds
* compound is distinct pure substance composed of atoms of two or more elements and contain exactly the same relative masses of those elements
* Rules for Writing Formulas
* each atom present is represented by element symbol
* number of each type of atom indicated by superscript written to right of element symbol
* when only one atom of a given type is present, superscript 1 is not written
* Structure of the Atoms
* Dalton's (1808) theory provided convincing explanation for composition of compounds that it was generally accepted
* people believed that atoms existed, did not have understanding of structure of atoms
* Plum Pudding Models
* J.J. Thomson (1890) atoms of any element can be made to emit tiny negative particles
* believed that is there is a negative there must be a positive to balance it out
* believed there was positive charge cloud with electron scattered to balance charge
* New Atomic Models
* Rutherford discovered when you hit an atom with a particle, there was a deflection
* suggested there was some sort of core to the atom
* if there was no core then particle will go straight through
* Parts of the Atom
* three parts- proton+, neutron, and proton
* electron has relative mass of 1 and charge of -1
* protons has relative mass of 1836 and charge of +1
* neuron has relative mass of 1839 and charge of 0
* Atomic Number
* atoms classified by atomic number (number of protons in nucleus)
* Isotope
* atoms of the same element having different numbers of neurons
* Mass Number
* approximately equal to number of protons plus number of neutrons
* Isotopes of Carbon with Atomic Mass
* carbon 12 has 6 protons and 6 neutrons
* carbon 13 has 6 protons and 7 neutrons
* carbon 14 has 6 protons and 8 neutrons
* protons stay the same and neutrons go up to meet number
* Mass Number and Atomic Number
* mass number of element is = to number of protons + number of neutrons
* ex. oxygen has 8 protons and 8 neurons, mass number is 16
* Periodic Tables
* atomic number, above chemical symbol, equal to the number of protons in nucleus
* number below is atomic mass
* Metals
* physical properties-
* efficient conduction of heat and electricity
* malleability (flatten into sheets)
* ductility (pulled to form a wire)
* lustrous (shiny) appearance
* Nonmetals
* lacks properties of metals
* nonmetal elements can be found in gas, liquid, and solid
* Ions
* electrically neutral atom, number of negatively charged electrons = number of positively charged protons
* when number of electrons in an atom differs from number of proton, atom is not longer neutral and has net charge
* atom with net charge is an ion
* States of Elements
* most elements reactive and combine to form new compounds
* some elements not reactive and can be found in pure elemental states
* nobel is term that is given to elements that have low reactivity
* nobel metals are gold, silver, and platinum
* nobel gases are all elements in group 8
* Diatomic Molecules
* some elements combine to themselves to form a molecule
* most molecules are gases at room temperature
* Allotropes
* non metals solids more varied than metals
* different forms of a given element
* Ions
* atoms that either gain or loose one or more electrons to form changed atoms
* cation is atoms that have lost one or more electrons forming a positive ion
* anion is atoms that gain one or more electrons to form negative ion
* Naming anion
* any element that becomes negative, dropping ine ending and adding ide to end
* Ionic Compounds
* both cation and anion must be present
* net charge of compound must be zero