WONDER #1338: Why Does Wood Crackle When It Burns?

Question 1 of 3

What basic element in the air is required for fire?

  1. oxygen
  2. nitrogen
  3. hydrogen
  4. helium

Question 2 of 3

A combustion reaction will occur when a source of fuel is heated to what point?

  1. boiling point
  2. melting point
  3. ignition temperature
  4. freezing point

Question 3 of 3

The decomposing cellulose material of burning wood takes several forms, including all but which of the following?

  1. volatile gases
  2. char
  3. ash
  4. bark

Check your answers online at https://wonderopolis.org/wonder/why-does-wood-crackle-when-it-burns.