Verified answer

Yomamanium. - The densest of all the elements. Just like yo mama. It's symbol would be a lightning bolt striking a panda... just because I would like to see textbook publishers have print it.

Ontopofthedresseranium - So I can have an easy way of remembering where I put my keys. It's symbol would be the outline of a 1987 Honda Civic key.

Hdyrogen - Looks like somebody typo-ed. It's symbol would be a lowercase h.