Here's why it's a range:
* The type of paper: Different paper types (e.g., thin paper, cardboard) have varying ignition temperatures.
* The surrounding environment: Factors like humidity, oxygen levels, and the presence of other flammable materials can affect the ignition temperature.
* The source of heat: A small flame might require a higher temperature to ignite paper than a strong source of heat.
While the average ignition temperature of paper is around 461°F (238°C), it's essential to remember it's a broad range and varies depending on the specific conditions.