Chapter 4: Elements, Atoms, and Ions
Elements:
- It has been found that all matter is broken down chemically into about 100 different elements.
- 116 elements have been discovered but only 88 of those are natural
- the body consists of 25 elements needed for us to live
- the naming of elements are derived from Greek and Latin
- first letter of the element is always capitalized
Website: http://www.chem4kids.com/files/elem_intro.html
This website goes into a deeper understanding of what the element is and how it is represented.
Dalton's Atomic Theory:
1. Elements are made of tiny particles
2. All atoms of a given element are identical
3. The atoms of a given element are different from those of any other element
4. Atoms of one element can combine with atoms of other elements to form compounds. A given compound always has the same relative numbers and types of atoms
5. Atoms are indivisible in chemical processes. That is, atoms are not create or destroyed in chemical reactions. A chemical reaction simply changes the way the atoms are grouped together
Compounds and Chemical Formulas
-compound: is a distinct substance that is composed of the atoms of two or more elements and always contains exactly the same relative masses of those elements
-chemical formulas: the types of atoms and the number of each type in each unit (molecule) of a given compound are expressed by a chemical formula
-in a chemical formula, the atoms are indicated by the element symbols and the number of each type of atom is indicated by a subscript
-how to write formulas:
1. each atom present is represented by its element symbol
2. the number of each type of atom is indicated by a subscript written to the right of the element symbol
3. when only one atom of a given type is present, the subscript 1 is not written
calculation:
10 oxygens, 4 phosphorus
answer: O10P4
activity:
naming chemical formulas - http://www.quia.com/rr/180365.html
A helpful game from Quia that can provide practice of naming chemical formulas.
websites:
naming compounds - http://www.emsb.qc.ca/laurenhill/science/name.html
A further understanding on how to name compounds.
writing formulas - http://www.kentchemistry.com/links/naming/formulawriting.htm
A helpful understanding on how to write formulas.
videos:
http://www.youtube.com/watch?v=JmCvGupU0IE
This video provides more information and examples on compounds and chemical formulas
Structure of the Atom
-current structure of the atom consists of protons (positive), neutrons (neutral), electrons (negative) and is classified by atomic number which is the number of protons and neutrons added up
-the old models are plum pudding which is atoms that can emit tiny negative particles and positive charge balances the negative charge, along with positive charge could of electrons to balance it all; alpha particles showed a deflection(something was keeping it from going straight through)
How an Element Can Change
-an element can change when it changes the number of protons
video:
http://www.brightstorm.com/science/chemistry/matter/elements-compounds/
This video shows and explains elements and how an element can change
How an Element Can Become An Isotope
-isotopes are atoms with the same number of protons but different numbers of neutrons; the different possible versions of an element
website:
http://ethomas.web.wesleyan.edu/ees123/isotope.htm
This website goes into further detail of understanding an element as an isotope and provides examples to make it easier to learn.
How an Element Can Become an Ion
-if there are more or less electrons in an atom than protons, it becomes an ion
website:
http://www.chem4kids.com/files/atom_ions.html
This website helps understand how an element can become an ion and gives examples for a deeper understanding.
How to Find the Amount of Protons, Electrons, and Neutrons in an Element
-the number of protons = atomic number
- number of electrons = number of protons
- number of neutrons = mass number - atomic number
website:
http://education.jlab.org/qa/mathnuceus_01.html
This websites provides information on how to identify the amount of protons, electrons, neutrons in an element from the periodic table.
activity:
http://education.jlab.org/elementmath/
This activity gives more practice on finding protons, electrons, and neutrons in an element.
video:
http://www.youtube.com/watch?v=cCvgbTGoUHU
This video provides a deeper understanding on finding the protons, neutrons and electrons in an element. It provides helpful examples on how to find these.
calculation:
element: krypton
number of protons = atomic number = 36
number of electrons = number of protons = atomic number = 36
number of neutrons = mass number - atomic number = 84-36 = 48
Different Groups of the Periodic Table
-first column: alkali metals
-second group of elements: alkaline earth metals
-seventh group elements: halogens
-eigth group of elements: noble gases
-most of the elements are metals
website:
http://chemistry.about.com/library/weekly/blgroups.htm
This website goes into a deeper understanding of the groups of the periodic table. It provides interactive visuals of the periodic table.
Physical Properties of Metals
1. efficient conduction of heat and electricity
2. malleability (they can be hammered into thin sheets)
3. ductility (they can be pulled into wires)
4. a lustrous (shiny) appearance
Diatomic Molecules
- molecules made up of two atoms
-examples:
Hydrogen (H2)
Nitrogen (N2)
Oxygen (O2)
Fluorine (F2)
Chlorine (Cl2)
Iodine (I2)
Bromine (Br2)
Examples of Allotropes
-two or more different forms of the same element in the same state is called allotropy and the forms are called allotropes of that element
examples:
-diamond and graphite are the allotropes of carbon
-O2 and O3, are allotropes of oxygen
How to Form Ionic Compounds from Ions
-an ionic compound is when a compound forms between a metal and nonmetal
-if a compound contains an ion then both positive ions (cations) and negative ions (anions) must be present
-the number of cations and anions must be such that the net charge is zero
calculations:
1. Na (charge 1+) Cl (charge -) --> NaCl
2. Mg (charge 2+) Cl (charge -) Cl (charge -) --> MgCl2
website:
http://www.occc.edu/kmbailey/chem1115tutorials/formulas_ionic.htm
This website helps understand how to form and name ionic compounds.
activity:
http://www.quia.com/quiz/1240133.html
This activity gives an opportunity to practice naming and forming ionic compounds, providing a deeper understanding.
video:
http://www.youtube.com/watch?v=hKCoXIjBrwg
This video provides helpful understandings on how to form and name ionic compounds.
Elements:
- It has been found that all matter is broken down chemically into about 100 different elements.
- 116 elements have been discovered but only 88 of those are natural
- the body consists of 25 elements needed for us to live
- the naming of elements are derived from Greek and Latin
- first letter of the element is always capitalized
Website: http://www.chem4kids.com/files/elem_intro.html
This website goes into a deeper understanding of what the element is and how it is represented.
Dalton's Atomic Theory:
1. Elements are made of tiny particles
2. All atoms of a given element are identical
3. The atoms of a given element are different from those of any other element
4. Atoms of one element can combine with atoms of other elements to form compounds. A given compound always has the same relative numbers and types of atoms
5. Atoms are indivisible in chemical processes. That is, atoms are not create or destroyed in chemical reactions. A chemical reaction simply changes the way the atoms are grouped together
Compounds and Chemical Formulas
-compound: is a distinct substance that is composed of the atoms of two or more elements and always contains exactly the same relative masses of those elements
-chemical formulas: the types of atoms and the number of each type in each unit (molecule) of a given compound are expressed by a chemical formula
-in a chemical formula, the atoms are indicated by the element symbols and the number of each type of atom is indicated by a subscript
-how to write formulas:
1. each atom present is represented by its element symbol
2. the number of each type of atom is indicated by a subscript written to the right of the element symbol
3. when only one atom of a given type is present, the subscript 1 is not written
calculation:
10 oxygens, 4 phosphorus
answer: O10P4
activity:
naming chemical formulas - http://www.quia.com/rr/180365.html
A helpful game from Quia that can provide practice of naming chemical formulas.
websites:
naming compounds - http://www.emsb.qc.ca/laurenhill/science/name.html
A further understanding on how to name compounds.
writing formulas - http://www.kentchemistry.com/links/naming/formulawriting.htm
A helpful understanding on how to write formulas.
videos:
http://www.youtube.com/watch?v=JmCvGupU0IE
This video provides more information and examples on compounds and chemical formulas
Structure of the Atom
-current structure of the atom consists of protons (positive), neutrons (neutral), electrons (negative) and is classified by atomic number which is the number of protons and neutrons added up
-the old models are plum pudding which is atoms that can emit tiny negative particles and positive charge balances the negative charge, along with positive charge could of electrons to balance it all; alpha particles showed a deflection(something was keeping it from going straight through)
How an Element Can Change
-an element can change when it changes the number of protons
video:
http://www.brightstorm.com/science/chemistry/matter/elements-compounds/
This video shows and explains elements and how an element can change
How an Element Can Become An Isotope
-isotopes are atoms with the same number of protons but different numbers of neutrons; the different possible versions of an element
website:
http://ethomas.web.wesleyan.edu/ees123/isotope.htm
This website goes into further detail of understanding an element as an isotope and provides examples to make it easier to learn.
How an Element Can Become an Ion
-if there are more or less electrons in an atom than protons, it becomes an ion
website:
http://www.chem4kids.com/files/atom_ions.html
This website helps understand how an element can become an ion and gives examples for a deeper understanding.
How to Find the Amount of Protons, Electrons, and Neutrons in an Element
-the number of protons = atomic number
- number of electrons = number of protons
- number of neutrons = mass number - atomic number
website:
http://education.jlab.org/qa/mathnuceus_01.html
This websites provides information on how to identify the amount of protons, electrons, neutrons in an element from the periodic table.
activity:
http://education.jlab.org/elementmath/
This activity gives more practice on finding protons, electrons, and neutrons in an element.
video:
http://www.youtube.com/watch?v=cCvgbTGoUHU
This video provides a deeper understanding on finding the protons, neutrons and electrons in an element. It provides helpful examples on how to find these.
calculation:
element: krypton
number of protons = atomic number = 36
number of electrons = number of protons = atomic number = 36
number of neutrons = mass number - atomic number = 84-36 = 48
Different Groups of the Periodic Table
-first column: alkali metals
-second group of elements: alkaline earth metals
-seventh group elements: halogens
-eigth group of elements: noble gases
-most of the elements are metals
website:
http://chemistry.about.com/library/weekly/blgroups.htm
This website goes into a deeper understanding of the groups of the periodic table. It provides interactive visuals of the periodic table.
Physical Properties of Metals
1. efficient conduction of heat and electricity
2. malleability (they can be hammered into thin sheets)
3. ductility (they can be pulled into wires)
4. a lustrous (shiny) appearance
Diatomic Molecules
- molecules made up of two atoms
-examples:
Hydrogen (H2)
Nitrogen (N2)
Oxygen (O2)
Fluorine (F2)
Chlorine (Cl2)
Iodine (I2)
Bromine (Br2)
Examples of Allotropes
-two or more different forms of the same element in the same state is called allotropy and the forms are called allotropes of that element
examples:
-diamond and graphite are the allotropes of carbon
-O2 and O3, are allotropes of oxygen
How to Form Ionic Compounds from Ions
-an ionic compound is when a compound forms between a metal and nonmetal
-if a compound contains an ion then both positive ions (cations) and negative ions (anions) must be present
-the number of cations and anions must be such that the net charge is zero
calculations:
1. Na (charge 1+) Cl (charge -) --> NaCl
2. Mg (charge 2+) Cl (charge -) Cl (charge -) --> MgCl2
website:
http://www.occc.edu/kmbailey/chem1115tutorials/formulas_ionic.htm
This website helps understand how to form and name ionic compounds.
activity:
http://www.quia.com/quiz/1240133.html
This activity gives an opportunity to practice naming and forming ionic compounds, providing a deeper understanding.
video:
http://www.youtube.com/watch?v=hKCoXIjBrwg
This video provides helpful understandings on how to form and name ionic compounds.