Generally the state of matter can be changed by two ways, 1.
When you are asking to convert 100 F to C, you are asking to convert 100 degrees Fahrenheit to degrees Celsius.
The Fahrenheit scale was adopted by the United States and also serves the same purpose.
He initially based the scale on an equal ice-salt mixture, selecting the values of 30°F for the freezing point of water, and 90°F for normal body temperature.
This unit is named after physicist Daniel Gabriel Fahrenheit who first proposed this temperature scale in 1724.
How to convert 100 Fahrenheit to Celsius 0 degrees Fahrenheit is equal to -17.