82. Eating raw onions are good for unblocking a stuffed nose.
Inaccurate. At most, eating raw onions is good therefor.

91. Hot water is heavier than cold water.
Of course, what they mean to say is, "Hot water is heavier than an equal volume of cold water;" that is, more dense. But that claim is untrue: if I recall my physics Chemeng1992, are you there?: the density of water rises as its temperature rises for 32 def. F. to 37 deg. F. but then falls with further termpature increases.

This is within the experience of anyone who has tried to heat a bathtub of too-cool water by adding hot water from the tap. The hot water stays on the top (is less dense), unless stirred.