The msds for propane gives it a health rating of 1, a flammability rating of 4, and reactivity rating of 0. according to the msds, which best describes propane

The answer is: highly flammable.

The Material Safety Data Sheet (MSDS) is a detailed fact sheet summarizing information about a chemical's hazardous ingredients.

Balanced chemical reaction of propane combustion:

C₃H₈ + 5O₂ → 3CO₂ + 4H₂O.

This is very exothermic reaction.

Chemical formula for propane is CH₃-CH₂-CH₃.  

Propane is a three carbon alkane (acyclic saturated hydrocarbon).

c is having 4 valence electrons and is bonded to three hydrogens and one sulphur atom, therefore, the number of bond pair is equal to four. as all the valence electrons are used in forming the bonds so, there is no lone pair left on carbon.

s is having 6 valence electrons and is bonded to one other sulfur atom and one carbon atom, therefore, the number of bond pair is equal to 2. as only two valence electrons are used in forming the bonds so, four electrons are left. therefore, two lone pairs are present on s.