What is the molality of a solution when 1 mole of nacl is dissolved in 250 ml of water?

What is the density of the black hole

Harvey kept a balloon with a volume of 348 milliliters at 25.0˚c inside a freezer for a night.  when he took it out, its new volume was 322 milliliters, but its pressure was the same.  if the final temperature of the balloon is the same as the freezer’s, what is the temperature of the freezer? the temperature of the freezer is  kelvins.

Adilute aqueous potassium nitrate solution is