2: Gravimetric Analysis of Phosphorous in Plant Food

Gravimetric Analysis

Mass measurement-based analytical method.

Phosphorous Content

Amount of phosphorous in fertilizers, expressed as P2O5.

Primary Nutrients

Essential nutrients: nitrogen, phosphorus, potassium.

Plant Food Labeling

Displays nutrient percentages: N-P2O5-K2O.

P2O5

Phosphorus pentoxide, indicates phosphorous content.

K2O

Potassium oxide, indicates potassium content.

Mass Percent Composition

Percentage of a component's mass in a mixture.

Precipitate

Solid formed from a solution during a chemical reaction.

Magnesium Ammonium Phosphate Hexahydrate

MgNH4PO4·6H2O, precipitate formed in analysis.

Neutralization

Reaction between acid and base to form salt.

Hydroxide Ion

OH⁻, used to increase solution pH.

Vacuum Filtration

Technique to separate solids from liquids using suction.

Activated Carbon

Used to remove colored impurities from solution.

Copper Cations

Cu²⁺ ions that can contaminate the precipitate.

Acidic Solution

Solution with a pH less than 7.

Room Temperature

Typically around 20-25°C, crucial for solubility control.

Filtrate

Liquid that passes through the filter during filtration.

Supernatant

Liquid above a settled precipitate after centrifugation.

Post-lab Exercise

Task to analyze results after the experiment.

Mass of Precipitate

Weight of the formed solid used for calculations.

Expected P2O5 Content

Anticipated percentage of phosphorous in fertilizer.

Standard Deviation

Statistical measure of data variability.

Percent Error

Difference between experimental and theoretical values.

Ecological Effects

Negative environmental impacts from excess nutrients.

Dilute Solution

Solution with a low concentration of solute.

Chemical Fume Hood

Ventilated enclosure for handling hazardous substances.

Buchner Funnel

Equipment used for vacuum filtration.

Miracle-Gro

Brand of water-soluble plant food analyzed.

Filtration Flask

Container used to collect filtrate during filtration.