90-110 is hand washing temp. 100 average.
110 is hot
120 recommend max
130 very hot
140 very very hot
150 burns
If I said to you. Would you stick your hand in 50°C water for 100 dollars would you do it?
What about 60°C?
65°C?
I bet you don't know what would happen if you stuck your hand in 65°C water without looking it up. There's a huge jump from 60° to 65°C. 70°C will instantly scald you.
Someone out there is stupid enough to think. Water boils at 100°C, 65 should be perfectly fine. Even though water doesn't boil until 212°, most people would be cautious of sticking their hand in 100°F+ water.
Yes if you think 40°C+ is hot then you can gather that 65°C would be hotter. But why compare to 40° when you can do 100°.
When do you use 0° and 100°C?
This is also at standard pressure and most do not live at sea level.
I don't put a thermometer in my water to make sure it is boiling or one in my water to make sure it freezes.
It can snow and roads can ice before it hits 0°C
It has no real world applications