Page 138 - The Periodic Table Book

31
Ga Gallium

Discovery: 1875
31 31 39 State: Solid
The Boron Group Diaspore Thermometer
Forms
Uses

This medical
thermometer uses
a gallium alloy
instead of mercury.

A gallium laser
is used to read
Blu-ray discs.

Blu-ray disc

The red LED
Red LED lights
gets its colour from
The needle-like crystals gallium compounds.
form on the surface.

Pure gallium
has a very low
melting point. Cube of melting gallium

Opportunity
rover

The solar panels powering this
rover, which is exploring Mars,
contain gallium and arsenic.

Gallium melts at just 29°C (84.2°F), which Gallium has a number of uses. It is mixed
means it soon becomes liquid when held with indium and tin to form a liquid alloy called
in the hand. This element is found in small galinstan, which can be used in thermometers.
amounts in ores of zinc and aluminium, such Gallium is also found in Blu-ray lasers, LEDs,
as diaspore. Pure gallium is isolated when and some solar panels, such as those on NASA’s
136 the other elements from this ore are extracted. Mars rovers.

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