What are the most common answers to “Name an actinide”?

Most people start with Uranium, Plutonium and Thorium. In Icillion they are worth 10 points each, the least of any level.

How many answers does Icillion accept for “Name an actinide”?

15 in all: 3 on The Tip, 4 Below the Surface, 4 in The Deep, 3 in The Abyss, and a single legendary answer Below the Iceberg.

The shortest accepted answer is “Curium” and the longest is “Protactinium”.

Chemistry trivia

Can you get past the obvious ones? Icillion accepts 15 answers to “Name an actinide”, and only 3 of them float on the tip of the iceberg.

Right, but shallow: 3 answers nearly everyone thinks of, worth 10 points each.

These 4 are known, but not the first thing people say. 25 points each:

The Deep holds 4 answers starting with B, E, N and P. The Abyss has 3 more, and one legendary answer waits below them all.

15 answers in total, every one of them a single word.
Shortest: “Curium”. Longest: “Protactinium”.
A, C and N are the most common first letters; together they start 40% of the answers.

How deep does your knowledge go?

Seven prompts a day, twenty seconds each. Obvious answers float on the tip of the iceberg; rare ones sink all the way to the trench.