Chemistry
The Periodic Table
Metals: Materials that conduct heat and electricity. They are malleable and shiny. They are solids at room temperature. Groups 1-14 are mostly metal.
Metaloids: Materials that have properties of both metals and nonmetals. Most of them are semiconductors. There are some metaloids in groups 13-17.
Non-metals: Materials that are poor conductors. They are not malleable, dull, and most are a gas at room temperature.
GROUPS-- columns of elements that have similar properties
PERIODS-- rows of elements that change gradually as it goes across. They are ordered by atomic number.
Metaloids: Materials that have properties of both metals and nonmetals. Most of them are semiconductors. There are some metaloids in groups 13-17.
Non-metals: Materials that are poor conductors. They are not malleable, dull, and most are a gas at room temperature.
GROUPS-- columns of elements that have similar properties
PERIODS-- rows of elements that change gradually as it goes across. They are ordered by atomic number.
How To Balance a Chemical Equation
Rules--
1) Subscripts can never be changed
2) Chemical Formulas can never be changed
3) You can only change the coefficient in the front of the formula
In order to have a balanced equation, you must have the same number of each atom on both sides.
Example:
Al + O2 yields Al2O3
Al= 1 Al= 2
O= 2 O= 3
To balance the equation, you must have an equal number of oxygen and aluminum on each side.
Remember to use the rules when balancing this equation!
12Al + 9O2 yields 6Al2O3
Al= 12 Al= 12
O= 18 O= 18
Rules--
1) Subscripts can never be changed
2) Chemical Formulas can never be changed
3) You can only change the coefficient in the front of the formula
In order to have a balanced equation, you must have the same number of each atom on both sides.
Example:
Al + O2 yields Al2O3
Al= 1 Al= 2
O= 2 O= 3
To balance the equation, you must have an equal number of oxygen and aluminum on each side.
Remember to use the rules when balancing this equation!
12Al + 9O2 yields 6Al2O3
Al= 12 Al= 12
O= 18 O= 18
Elements, Molecules, and Compounds
Elements-- most basic unit of matter and cannot be broken down into simpler substances; pure substance; Example: Al
Molecules-- combination of two or more elements; Example: O2
Compounds-- combination of two or more different elements; have its own characteristics; Example: NaCl
*note that all compounds are molecules but not all molecules are compounds
Elements-- most basic unit of matter and cannot be broken down into simpler substances; pure substance; Example: Al
Molecules-- combination of two or more elements; Example: O2
Compounds-- combination of two or more different elements; have its own characteristics; Example: NaCl
*note that all compounds are molecules but not all molecules are compounds
Density, Mass, and Volume
Density-- The amount of mass per unit of volume; how much matter is in a given space (Density = mass / volume)
Mass-- The amount of matter in an object (Mass = Density x Volume)
Volume-- The amount of space that an object takes up (Volume = length x width x height) *Volume of irregular objects can also be found by measuring the amount of water that the object displaces
Density-- The amount of mass per unit of volume; how much matter is in a given space (Density = mass / volume)
Mass-- The amount of matter in an object (Mass = Density x Volume)
Volume-- The amount of space that an object takes up (Volume = length x width x height) *Volume of irregular objects can also be found by measuring the amount of water that the object displaces
Looking for the important words with chemistry? Check out the Words to Know tab which is located to the left of the chemistry tab when you hover your mouse!
Works Cited
Atom. Digital image. Sparkfun. N.p., n.d. Web. 24 Feb. 2017.
Hydrogen and Oxygen Bond. Digital image. Chemical Principals. N.p., n.d. Web. 24 Feb. 2017.
The Periodic Table. Digital image. Middlebury. N.p., n.d. Web. 26 Feb. 2017.
The Periodic Table with Colored Labels. Digital image. Science Notes. N.p., n.d. Web. 21 Feb. 2017.
Atom. Digital image. Sparkfun. N.p., n.d. Web. 24 Feb. 2017.
Hydrogen and Oxygen Bond. Digital image. Chemical Principals. N.p., n.d. Web. 24 Feb. 2017.
The Periodic Table. Digital image. Middlebury. N.p., n.d. Web. 26 Feb. 2017.
The Periodic Table with Colored Labels. Digital image. Science Notes. N.p., n.d. Web. 21 Feb. 2017.