Jeopardy: Sustainable Aluminum in a Nutshell

Production

100

This is the first step in the aluminum refinement process, where ore is heated and dissolved under pressure in sodium hydroxide

Bayer process

200

These two oxides are the primary targets for removal during the Bayer process

Iron and silicon oxides

300

This is the second step in the aluminum refinement process, named after the two people who discovered it independently in 1886

Hall-Heroult process

400

In the second step of refinement, this compound is formed by oxidizing the consumable anode of the electrolytic reduction cell

Carbon dioxide (CO₂)

500

The addition of this substance during the second step in aluminum refinement is for the purpose of reducing the melting temperature and increasing electrical conductivity

Cryolite (hexafluoroaluminate, Na₃AlF₆)

Properties

100

This property is a ratio of a material's strength to its mass density; in this regard, aluminum outperforms steel

Specific strength

200

This property of aluminum makes it preferable to plain carbon steel in applications such as marine vessels, beverage cans, and eating utensils

Corrosion resistance

300

This property is the degree of plastic deformation before fracture; it can be measured with percent elongation or percent reduction in cross-sectional area

Ductility

400

Although aluminum is the third most abundant element in Earth's crust, extraction is difficult and primarily carried out on this one ore

Bauxite

500

In this regard, aluminum only has about two thirds the ability of copper, but around five times that of plain steel

Electrical conductivity

Uses

100

Due to aluminum's ability to be stamped into shapes and its comparatively low density, it is increasingly replacing this metal in the automotive industry

Steel

200

In this application, aluminum is more optimal than copper because of its combination of light weight and good electrical conductivity

Power lines

300

Alloying aluminum with this alkali metal produces alloys that are lightweight and stiff, but very expensive

Lithium

400

The formation of this compound on aluminum's surface protects the bulk metal from corrosion when used in marine applications

Aluminum oxide (Al₂O₃)

500

Before the invention of airplanes, aluminum was used for the frames of these flying machines

Zeppelins

Sustainability

100

This property of red mud makes it an environmental hazard on par with household bleach if stored incorrectly

Alkalinity

200

DOUBLE JEOPARDY

Coating the cathode with this titanium-containing compound during the Hall-Heroult process increases the efficiency of aluminum production

Titanium diboride (TiB₂)

300

This amount of bauxite is required to produce 1 ton of pure aluminum metal

3.5-4 tons

400

The production of 1 ton of aluminum metal via the Hall-Heroult process produces this many tons of carbon dioxide

8 tons

500

Recycling aluminum requires about this percent of the energy needed to produce new aluminum

5%

Trivia

100

Neutral aluminum has this number of valence electrons

3 valence electrons

200

Because aluminum has this crystal structure, it is more malleable and ductile than some other metals (such as zinc or iron)

FCC (face-centered cubic)

300

This country is the world's top producer of aluminum, with a 55% share of global production

China

400

Aluminum is the third most abundant element in Earth's crust, only exceeded in weight percent by these two elements

Oxygen and silicon

500

Due to its ability to react as both a Lewis acid and Lewis base, aluminum oxide can be classified as this type of compound

Amphoteric