Applied Chemistry Question Bank - Polymers, Water Chemistry, and Engineering Materials

Practice flashcards covering definitions and properties from polymers, water chemistry, analytical techniques, and engineering materials based on the lecture question bank.

Number Average Molecular Weight ($\bar{M}_n$)

The total weight of all the polymer molecules in a sample, divided by the total number of molecules in a sample.

Weight Average Molecular Weight ($\bar{M}_w$)

Sum of the products of total mass of groups of molecules and their respective molecular mass divided by the total mass of all the molecules.

Polyvinyl Chloride (PVC)

A versatile thermoplastic polymer prepared by addition polymerization from starting materials acetylene and $HCl$, via a vinyl chloride monomer stage.

PVC Melting Point

The temperature at which Polyvinyl Chloride melts, specifically $212\,^{\circ}\text{C}$.

Polymer Composite

A material made of two or more types of polymers with different physical and chemical properties that combined produce characteristics different from individual components, such as KEVLAR-EPOXY.

KEVLAR

A crystalline, lightweight, and non-flammable polymer resistant to heat, impact, and scratch; used in products like bulletproof vests and car tires.

Hardwater

Water which does not produce lather easily with soap.

Desalination

The process of removing salt from saline or brackish water.

Reverse Osmosis (RO)

The process of movement of water through a semi-permeable membrane from higher concentration to dilute solution with the application of pressure greater than osmotic pressure.

Chemical Oxygen Demand (COD)

A measure of the oxygen required to chemically oxidize organic pollutants, calculated using the dichromate method with the formula $\frac{N_{FAS} \times (b-a) \times 8000}{V_{sample}}$, where "b" is the blank titration and "a" is the sample titration.

Water Softening

The process of removing hardness-causing salts from water, often utilizing cation exchange resins ($RH^+$) and anion exchange resins ($R'OH^-$).

Potentiometric Redox Titration

A method to estimate iron concentration using a platinum indicator electrode and calomel reference electrode, where potential is measured based on the Nernst equation: $E = E^o + \frac{0.0591}{n} \log\left(\frac{[Fe^{3+}]}{[Fe^{2+}]}\right)$.Check for exactness.

Conductometry

An analytical technique based on Ohm's law ($E = IR$) where the measurement of solution conductance depends on the number, charge, and mobility of ions.

Alnico

A heat-treated alloy of $Fe-Al-Ni-Co-Cu$: specifically aluminum ($8\%-12\%\text{Al}$), nickel ($15\%-26\%\text{Ni}$), cobalt ($5\%-24\%\text{Co}$), iron ($50\%\text{Fe}$), copper ($6\%\text{Cu}$), and titanium ($1\%\text{Ti}$).

Perovskite (General Formula)

A material with the chemical structure represented by the general formula $ABO_3$, such as Calcium titanium oxide ($CaTiO_3$).

Ceramic Materials

Inorganic, non-metallic materials processed at high temperatures that are hard, wear-resistant, brittle, and typically good insulators.

Silicate Ceramics

Materials primarily composed of silicon and oxygen, including porcelain, glass, and fire clay brick.

Oxide Ceramics

Material types including alumina ($Al_2O_3$), zirconia ($ZrO_2$), and magnesia ($MgO$).

Non-Oxide Ceramics

Ceramic materials composed of compounds like carbon, nitrogen, boron, or silicon, such as silicon carbide ($SiC$) and silicon nitride ($Si_3N_4$).

Refractory

A chemical substance that is difficult to fuse and can withstand high temperatures without deformation under working conditions.

Acidic Refractories

Refractories made of materials like alumina and silica that are resistant to acid slags but attacked by basic slags.

Basic Refractories

Refractories composed of materials like $CaO$ and $MgO$ used in steelmaking open-hearth furnaces.

Neutral Refractories

Refractories made from weakly basic or acidic materials like carbon, zirconia, and chromite that resist both basic and acidic materials.

Refractoriness

The ability of a material to withstand high temperature without deformation under working conditions.

Thermal Spalling

The peeling, cracking, fracturing, or breaking of a refractory material.

Clinker

A nodular form of recombined lime, silica, and alumina produced during the cement manufacturing process after the heating stage.