My illustrious flatmate, a student of chemistry, pursuing her masters degree, walks up to the professor, to take her viva exam.

"This thing you are wearing.." he starts

She scans herself from head to toe. "Which one sir?"

"Lab coat"

"Oh"

"What would happen if acid fell on it?"

"A hole, sir" prompt reply.

"CHEMISTRY" he thunders.

She blinks.

"What would happen in the language of chemistry?"

"Oh.......Don't know."

"What is the formula for cotton?"

"Don't know."

"For silk?"

"Don't know."

"Where does silk come from?"

"Silk worm." prompt reply

"CHEMISTRY!"

"Oh.......Don't know."

He gives up.