Question | Answer |
mole | when we measure we often assign names to #s; represents a non-user friendly # |
1 mole = ? | 12g of C-12 |
avagadro's # | 6.02*10^23 |
few= | 3 |
millenium | 1000 |
googol | 10^100 |
does 1 mole of pennies=1 mole of gold? | NO |
does a mole of bricks weigh more or less than a mole of feathers? | more than |
molar mass | what 1 mole of something would weigh |
when do you use mole conversions | when you cannot easily count individual atoms; to convert between moles, molecules, and grams |
if you cannot count the atoms individually, then how do you count the atoms? | by weighing individual variables |
what is the t-chart for unit conversions? | what you have units of what you want
------------------ x ------------------------------
1 units of what you have |
what are the conversion factors for moles, atoms/molecules, molar mass, and liters? | moles=1, atoms/molecules=6.02*10^23, grams=molar mass, liters=22.4 |
avagadro's hypothesis | when talking about gases, the amount of space that 1 mole occupies will always be the same |
why can liquids and solids take up different amounts of space (each solid and liquid) | each atom is differently sized and packed |
how can the volume that gas takes up change? | it can change dependent on heat and pressure (increase temp.=expand) |
under what condition will avagadro's hypothessis work? | if the heat and pressure are constant (STP) |
STP | standard temperature and pressure |
what is the standard temperature and pressure? | 1 atomsphere (atm) at 0 degrees C, and at sea level |
what does the mole bridge look like now | Liters
|
grams---mole---atoms/molecules |
empirical formula | the reduced formula (ionic) |
molecular formula | the real amount of atoms present (covalent) |
4 steps to determine % composition | 1) percent to mass 2)mass to mole 3) divide by small 4) multiply till whole |
hydrates | a solid compound that contains water molecules in its crystal form |
efflorescent | water is not attached well and can be lost to the air |
hygroscopic | water can be pulled out of the air into the compound |
deliquescent | absorbs so much moisture that it becomes a liquid |
anhydrous | when a hydrate has been dried out |
how to find the formula of hydrates | convert the wet and dry substance into moles, then divide by small |