Freezing Temp. of water At different elevations?

Answer 1

Unlike boiling water freezes at the same temp regardless of air pressure (altitude).

However at very low air pressures such as outer space the water may boil directly from the ice to water vapor without becoming a liquid.

Answer 2

Elevation doesn't affect the freezing point. The chemicals like salt will lower the freeze point. Normal water freezes at 32 deg. F. salt water is about 26 deg. F.