The Phase Diagram for Helium

question 128

Multiple Choice

The phase diagram for helium

• A) indicates that helium exists as He(g) and He(l) at about 2 K.
• B) indicates that helium exists only as a gas.
• C) has two triple points.
• D) indicates that helium can be liquefied at ordinary pressures.
• E) indicates that helium has three phases.

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Definitions:

Trophic Level

Position of an organism in a food chain.

Chaparral Biome

A biome characterized by dense, spiny shrubs and a Mediterranean climate, with hot, dry summers and mild, wet winters, typically found in California and the Mediterranean region.

Primary Production

The rate at which an ecosystem’s producers capture and store energy.