Page 35 - The Periodic Table Book

Uses RUBIDIUM-STRONTIUM DATING

About a quarter of all rubidium atoms are radioactive.
Slowly over time, they break down into strontium atoms.
These lenses contain rubidium, Comparing the amounts of these elements in a rock
which aids night vision. shows when that mineral was formed. Older rocks have
less rubidium and more strontium in them.

Rubidium-87 atoms Only small amounts
(red) decay at a of strontium-87 The amount of
predictable rate. (blue) in the rock. strontium-87 has Alkali Metals
increased over time.

Millions Present day
of years ago

Night-vision goggles

Electricity cables
are hung from these
Photomultiplier
The structure of rubidium-rich
the brain can be seen This sensitive device insulators.
clearly because of the use detects light by using a
of radioactive rubidium. rubidium compound.
Ceramic insulator

Fireworks

PET scan

This purple colour comes
from burning a nitrogen
rubidium compound.

Magnetometer
This device from the early 20th century used
rubidium to measure the strength of magnetic fields.

rubidium in it but is very rare. Rubidium atoms are patient’s body, rubidium targets tumours, which
sensitive to light and can be used in photoelectric show up clearly on PET (positron emission
cells (devices that convert light energy into tomography) scans. Rubidium is also used by
electricity) and night-vision equipment. This light-sensitive electronics called photomultipliers,
element has radioactive forms, which can be used and in making insulators for high-voltage
to measure the age of rocks. When injected into a cables and some special types of glass. 33

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