Nobel Medals and Chemistry in WWII

In the 1930s, Nobel laureates Max von Laue and James Franck sent their gold medals to Niels Bohr in Denmark to protect them from the Nazis. Chemist George de Hevesy dissolved the medals in aqua regia to hide them. Aqua regia, a mix of nitric and hydrochloric acids, can dissolve gold by shifting the reaction equilibrium. After WWII, de Hevesy recovered the gold, and the medals were remade. This story highlights the chemistry of noble metals and the clever use of chemical reactions to solve real-world problems.

Why did Max von Laue and James Franck send their Nobel medals to Niels Bohr?

• To donate them to a museum

• To sell them for money

• To protect them from being stolen by the Nazis

• To exchange them for other valuables

What makes a metal 'noble'?

• Its magnetic properties

• Its ability to conduct electricity

• Its resistance to chemical reactions

• Its high melting point

Which of the following is NOT considered a noble metal by physicists?

• Silver

• Copper

• Iron

• Gold

What is the role of nitric acid in aqua regia?

• To pry off gold atoms

• To neutralize hydrochloric acid

• To dissolve glass

• To provide chloride ions

What happens when hydrochloric acid is added to the reaction with gold ions?

• It stops the reaction

• It forms a new metal

• It forms tetrachloroaurate

• It evaporates

How was the gold hidden during the war?

• It was hidden in a safe

• It was melted into a statue

• It was buried underground

• It was dissolved in a solution

What form did the gold take while it was hidden?

• Chloroauric acid

• Gold dust

• Gold coins

• Gold bars

How was the gold eventually recovered from the solution?

• By evaporating the liquid

• By filtering the solution

• By adding a chemical to reverse the reaction

• By heating the solution

What did the Nobel Foundation do with the recovered gold?

• They kept it in a vault

• They donated it to a museum

• They made new medals

• They sold it

What is the main theme of the video?

• The chemistry of noble metals

• The history of the Nobel Prize

• The rise of the Nazi party

• The clever use of chemistry to solve a problem