氮

Mnemonic symbol: a balloon. The Queen of Hearts is disappointed by her balloons. She expected them to float upwards, but in the space station's bathroom, They float randomly in all directions.

炎 = 火 : Mnemonic symbol: As I just learned "itis" is the feeling you get after eating too much.

炎 = 火 : Maud Younger ate too much just inside anthill. She's sleeping so hard that she doesn't even wake up from the fire which is spreading fast.