Does the freezing point of water change with atmospheric pressure as does the boiling point?
Ice skating is a good example of the fact that increased pressure decreases the freezing point of water (the opposite effect to boiling where increased pressure increases the boiling point) This reverse effect only occurs for a few degrees below zero. The pressure of the blade lowers the freezing point and causes the ice to melt – the skater is actually sliding on water. If the ice gets colder than a few degrees below zero, you can’t skate at all because the ‘reverse’ effect returns to normal.
