Flashcards in things to remember Deck (11):

1

## x

### mass of compound/ mass of empirical formula

2

## moles

### n = m (mass)/M (Molar Mass)

3

## moles (from atoms)

### n = N (particles)/ Na (Avogadro)`

4

## To find mass of excess reactant unreacted

### calculate moles reacted then subtract total amount by the amount reacted. times this by M

5

## molecular vs. empirical

###
molecular: how many atoms of each element in a compound

empirical: the simplest and most reduced RATIO of atoms in a compound

6

## steps for hydrate given a percentage of one Element

###
1) do the ratio (percent given/mass of element times ()percent x/ ()mass of element.). repeat for number of elements in compound

2) add up percentages, 100-x = percent hydrate

3) assume 100g, find moles, divide by smallest= EF

7

## percentage yield (What is it, find moles unreacted)

###
is also a ratio

write down everything. to find amount unreacted, find reacted amount (()mol times mol/()mol of other reactant ) then subtract total amount - reacted to get mol unreacted. times by M to get moles excess unreacted

8

## why do you divide by lowest number of moles in EF?

### divide because you want to find out how many particles are bonded to each particle of the lowest # of moles

9

## what does chemical formula give you

### relative amounts of particles/moles. balanced eqn is needed because it shows the amount of moles in relation to different products

10

## how to go from atoms to mass and back

###
Order: # of atoms- # of molecular - Moles - mass

EQN: (chemical formula, avogadro, Molar mass)

11