[ZJJK05-01-X]天然气与空气混合体积比浓度达到时,遇到火源会发生爆炸（）

A. 5%～15%

B. 5％～10％

C. 10％～15％

D. 5％～20％

A. 混合物中天然气浓度越高，越容易发生爆炸

B. 混合物中天然气浓度越高，越容易发生爆炸

C. 在与明火接触的条件下，只要空气中含有天然气就会发生爆炸

D. 混合物中天然气浓度在一定范围内

B．不能

B.2~3

C.5~15

D.0.5~1.5

A. 3％-4％

B. 2％-3％

C. 5％-15％

D. 0.5％-1.5％

天然气和空气混合，当天然气浓度在一定范围内时，遇明火就会发生燃烧和爆炸。燃烧时，燃烧波的传播速度较慢，约0.3～2.4m/s，而爆炸时，会迅即产生高压高温，波速达到1000～3000m/s，对管线和容器的破坏力很大。天然气产生爆炸的浓度范围为5～15％，随温度、压力升高，爆炸浓度的上限提高，爆炸范围扩大。Natural gas and air mix, when the concentration of natural gas within a certain range, open fire will occur combustion and explosion. In combustion, the propagation speed of combustion wave is slow, about 0.3 ~ 2.4m/s, while in explosion, the high pressure and temperature will be generated immediately, and the wave speed reaches 1000 ~ 3000m/s, which is very destructive to pipelines and containers. The explosion concentration range of natural gas is 5 ~ 15%. With the increase of temperature and pressure, the upper limit of explosion concentration increases and the explosion range expands.

此题为判断题(对，错)。