Final answer:
Always use a multi-class fire extinguisher to put out a tire fire, as water can spread flammable materials and CO2 extinguishers have limitations such as not being effective on magnesium fires.
Step-by-step explanation:
When dealing with a tire fire, one must never use water due to the risk of spreading flammable materials and the potential for a steam explosion. Rather, the best option would be to use a multi-class fire extinguisher that is appropriate for class B fires, which include flammable liquids and gases, which a tire fire can generate. Carbon dioxide extinguishers can be effective as they displace oxygen, thus smothering the fire. However, for a tire fire, larger-scale firefighting tools that can apply a foam that smothers and cools the fire are preferred.
The chemical reaction 2Mg(s) + CO₂(g) → 2MgO(s) + C(s) demonstrates that carbon dioxide is not effective in extinguishing certain types of metal fires, like magnesium, which is not applicable in the case of a tire fire but showcases the limitations of CO₂ extinguishers.