Q 01/05

Rubidium was named by its discoverers for which color of the bright lines in the light it emits?

A) Red

B) Yellow

C) Green

D) Blue

Answer · why

A) Red

Red is the answer: the name comes from rubidus, meaning deep red, after bright lines in its spectrum that matched no known element.

Q 02/05

Rubidium metal melts at about 39 °C, only a couple of degrees warmer than which of these?

A) A household freezer

B) A cup of hot tea

C) The human body

D) A kitchen oven

Answer · why

C) The human body

The human body runs at about 37 °C, which makes rubidium one of only five metals that are liquid at or near room temperature, alongside mercury and ga...

Q 03/05

Which element sits immediately before rubidium, element number 37, in the periodic table?

A) Bromine

B) Krypton

C) Selenium

D) Yttrium

Answer · why

B) Krypton

Krypton shares its name with Superman's home planet, and radioactive rubidium-82 decays into it within minutes.

Q 04/05

Rubidium sounds rare, yet it is more abundant in Earth's crust than which of these everyday metals?

A) Iron

B) Aluminium

C) Copper

D) Magnesium

Answer · why

C) Copper

Copper is scarcer in the crust than rubidium, which only seems rare because it never gathers into rich ores of its own.

Q 05/05

Doctors inject short-lived radioactive rubidium-82 to picture how well blood is reaching which organ?

A) Heart

B) Liver

C) Kidneys

D) Lungs

Answer · why

A) Heart

The heart muscle soaks up rubidium-82 in step with its blood supply, and with a half-life of barely over a minute the tracer must be made beside the p...