According to Xinhuanet, Los Angeles, June 1, 28: A fire broke out in Universal Studios Los Angeles on the 1 ST, including several location studios and photography that simulated street scenes in new y

According to Xinhuanet, Los Angeles, June 1, 28: A fire broke out in Universal Studios Los Angeles on the 1 ST, including several location studios and photography that simulated street scenes in new york. (1) Combustible combustion requires two conditions: contact with oxygen, and the temperature reaches the ignition point of combustible;

(2) The dry powder (mainly composed of NaHC3) in the dry powder fire extinguisher decomposes into sodium carbonate, water and carbon dioxide when heated, and is balanced by observation. The reaction condition is heating, so the chemical equation of the reaction is:

2NaHC3? △? .? Na2C3+H2+C2↑；

(3) When the fuel tank is heated, the temperature rises, and the pressure of combustible materials in the tank increases, and the tank can't bear the pressure, so the explosion will occur.

So the answer is: (1) Contact with oxygen; The temperature reaches the ignition point of combustible materials; （2）2NaHC3? △? .? Na2C3+H2+C2↑； (3) When the temperature rises, the pressure of combustible materials in the tank increases, and the tank can't bear the pressure, so the explosion will occur.