Question

Pyrophoric Materials can ignite when exposed to air ?

A) They can ignite when exposed to air.
B) They only ignite in the presence of an open flame.
C) They are entirely non-flammable.
D) They require extreme temperatures to ignite.

Answer 1

Pyrophoric materials ignite spontaneously upon exposure to air without any external ignition source due to their low activation energy and high reactivity with oxygen.

Step-by-step explanation:

Pyrophoric materials are substances that can ignite spontaneously when exposed to air, as they have a low activation energy and react rapidly with atmospheric oxygen.

The correct answer is A) They can ignite when exposed to air. A common trait among pyrophoric materials is that they catch fire without the need for an external flame or spark.

This contrasts with other materials, which require a significant heat source, such as an open flame, to overcome the activation energy needed for combustion, similar to the way a match ignites paper.

Unlike pyrophoric materials, combustible materials like paper or wood often need to be heated to a point where they reach the activation energy for combustion.

In the case of fireworks or a burning log, sufficient heat must be applied to start the reaction, making them distinct from pyrophoric materials that ignite at room temperatures due to their high reactivity with oxygen.