A Washington Post report pointed to a violent chemical reaction as the likely cause of the explosion at the Iranian port that killed at least 70 people.

When any substance burns in oxygen it is called a combustion reaction. Potassium (lilac) burns most vigorously followed by sodium (orange-yellow) and then lithium (red), as you might expect.

The New York Times reported Sunday that a person “with ties to Iran’s Islamic Revolutionary Guard Corps said that what exploded was sodium perchlorate ... been part of a reaction.” ...