The+Mole

Objectives:
1. Describe how Avogadro's number is related to the mole of any substance.

2. Calculate the mass of a mole of any substance.

3. Be able to use the following terms when describing the amount of a substance: mole, Avogadro's number, representative particle, gram atomic mass, gram molecular mass, gram formula mass.

__**THE MOLE- THE BASIC STUFF:):):)**__ The **mole** (symbol: mol) is the [|SI] base unit that measures an [|amount of substance]. The mole is a counting unit. One mole contains [|Avogadro's number] (approximately [|6.02214 × 1023]) entities (atoms, molecules, elemental particles).

A mole is much like ‘a dozen’ in that it can describe any type of elementary object (object made up of atoms or molecules, ions and formula units) For example, one mole of [|water] is equivalent to 18.016 grams of water and contains one mole of H2O molecules, but three moles of atoms (two moles H and one mole O).

__ Utility of moles __
== The mole is useful in [|chemistry] because it allows different substances to be measured comparably. Using the same number of moles of two substances, both amounts have the same number of [|molecules] or [|atoms]. The mole makes it easier to interpret chemical equations in practical terms. Thus the equation: == 2H2 + O2 → 2H2O can be understood, as "two moles of hydrogen plus one mole of oxygen yields two moles of water." Moles are useful in chemical calculations because they enable the calculation of yields and other values when dealing with particles of different mass. Number of particles is a more useful unit in chemistry than mass or weight, because reactions take place between atoms (for example, two hydrogen atoms and one oxygen atom make one molecule of water) that have very different weights (one oxygen atom weighs almost 16 times as much as a hydrogen atom). However, the raw numbers of atoms in a reaction are not convenient, because they are very large; for example, one [|mL] of water contain over 3.34 × 1022 molecules. http://dbhs.wvusd.k12.ca.us/webdocs/Mole/MolarMass.html

1.)How many moles of bromobenzene are in 1 kilogram of bromobenzene, C6H5Br? 2.)What is the mass in grams of neon gas that occupies a volume of 5 liters at 0° C and 1 atmosphere of pressure? 3.)Which has more mass: 1/2 a mole of Beryllium (He) or 3 moles of hydorgen (H)? 4.)If you have 1/2 a mole of Carbon and 1 mole of Oxygen, how many more moles would you need to make one mole of Carbon dioxide? which substance would need the extra particles?
 * __Practice problem__**