# Stoichimetry

### Mole-Mole & Mass-Mass Conversions

## Definition of Stoichimetry

Derives from two Greek words:

*stoicheion*(meaning "element") and*metron*(meaning "measure"), usually appeared as proportional units and being calculate using dimensional analysis to determined the quantities of the "unknown" based on the "given".## Aluminum reacts with Iron Oxide to produce Aluminum Oxide and Iron *Single Replacement*

## Mass to Mass Calculations 12.1 g of AluminumGiven:grams of IronPredict: 12.1(g) *2 moles*56(g) _________________________= 25.1 grams27(g)*2 moles | ## Moles to Moles Calculations 7.21 moles of AluminumGiven: moles of IronPredict:7.27 moles *2 mole --------------------------= 7.27moles2 moles | ## Limiting & Excess to find Theoretical Yield 12.1g of Al (A1)Given:20.15g of Fe2O3 (A2) IronPredict:A1: 12.1g*2 moles* 56g --------------------------=25.1g 27g*2 moles A2: 20.15g*2 moles*56g ----------------------------=14.11 g 160g A2 is limiting reactant, so 14.11 g isConclusions:theoretical yield. A1 is excess reactant |

## Mass to Mass Calculations

__12.1 g of Aluminum__

**Given:****grams of Iron**

__Predict:__12.1(g) *2 moles*56(g)

*_________________________*=

**25.1 grams**

27(g)*2 moles

## Moles to Moles Calculations

__7.21 moles of Aluminum__

**Given:**__moles of Iron__

**Predict:**7.27 moles *2 mole

--------------------------=

**7.27moles**

2 moles

## Limiting & Excess to find Theoretical Yield

__12.1g of Al (A1)__

**Given:**20.15g of Fe2O3 (A2)

__Iron__

**Predict:**A1: 12.1g*2 moles* 56g

--------------------------=25.1g

27g*2 moles

A2: 20.15g*2 moles*56g

----------------------------=14.11 g

160g

__A2 is limiting reactant, so 14.11 g is__

**Conclusions:**theoretical yield. A1 is excess reactant

## Percent Yield

__(Actual Yield/Theoretical Yield) * 100%__

**Formula:**__6.5g of Actual Yield__

**Given:****Percent Yield of Fe2O3**

__Predict:__(6.5 g/14.11g) *100%=

**46%**

Stoichiometry: Chemistry for Massive Creatures - Crash Course Chemistry #6