Beyond the answers - interesting background to this quiz

Why carbon gets a single letter

Carbon's chemical symbol is simply C, which makes it easy to confuse with calcium, whose symbol is Ca. In the periodic table, many symbols come from Latin or Greek names, but carbon's symbol is a direct abbreviation of its English name. As the basis of organic chemistry, carbon appears in an extraordinary range of substances, from graphite and diamond to the molecules that make up living cells.

The iris and the colour hazel

Hazel is not a fixed pigment but a description of an iris that combines shades of brown, green and sometimes amber. The appearance can shift depending on lighting, clothing or surrounding colours, which is why hazel eyes are often described as changeable. Eye colour is determined mainly by the amount and distribution of melanin in the iris, and hazel sits between lighter green or blue eyes and darker brown ones.

Ernest Hemingway and the 1954 Nobel Prize

Ernest Hemingway received the Nobel Prize in Literature in 1954, a year after the award had been withheld because no suitable candidate was found, according to the Swedish Academy's rules. The committee cited his mastery of narrative art and his influence on contemporary style. Hemingway did not travel to Stockholm for the ceremony; he sent a brief message that was read on his behalf.