ok it doesn't look like a hard but this salt and ice challenge freezes your hand so much it ends up burning your hand, it carries on stinging after for another 10 minutes.
The salt and ice challenge is a YouTube phenomenon wherein participants pour salt on their bodies, usually on the arm and ice is then placed on the salt.This causes a "burning" sensation, and participants vie to withstand the pain for the longest time. The challenge is recorded and posted on YouTube or other forms of social media. The salt causes the ice, lowering the freezing temperature, to melt and in the process absorbs heat from the environment (including a participant's hand). As a result, skin temperature drops far more than with ice alone, even though the temperature of the ice is the same. This can quickly cause second and third-degree injuries similar to frostbite. Due to the numbing sensation of the cold and possible nerve damage during the stunt, participants are often unaware of the extent of any injuries sustained during the challenge. Skin discoloration from the challenge may remain after the challenge has been attempted.