Lab 5 - Empirical formula AF 092324 - Recitation w Quiz

Empirical Formula

The simplest formula derived from measuring the stoichiometric amounts of reagents in forming products.

Molecular Formula

Contains the actual number of each atom in a compound.

Limiting Reagent

The reagent that is completely used up in a chemical reaction.

Excess Reagent

Reagent not completely used up in a chemical reaction; will be left over.

Stoichiometric Amounts

The quantities of reactants and products according to the balanced chemical equation.

Molar Mass

The mass of one mole of a substance, usually expressed in grams per mole (g/mol).

Conservation of Mass

The principle that mass is neither created nor destroyed in a chemical reaction.

Percent Error

A measure of the accuracy of a measurement, calculated as (observed - actual) / actual x 100.

Mole Ratio

The ratio of the amounts of moles of the substances involved in a reaction.

Zn + I2 → ZnxIy

A general representation of the reaction between zinc and iodine to form zinc iodide.

7 Na + S → Na?S?

A sample reaction representing sodium and sulfur combining to form sodium sulfide.

Safety Precautions

Measures taken to prevent exposure to hazardous substances; includes working under a hood and cleaning spills.

Decant

To pour off a liquid while leaving the solid at the bottom of the container.

Reactivity

The tendency of a substance to undergo chemical reactions.

Analytical Balance

A high-precision instrument for measuring mass.

Baker's Yeast

A common name for Saccharomyces cerevisiae, primarily used in baking and brewing.

Iodine Crystals

Solid form of iodine that can react with metals like zinc.

Methanol

A solvent commonly used in chemistry, known for its low boiling point.

Zinc Iodide

A chemical compound formed from the reaction of zinc and iodine.