Strong Acid has a lower pH level than a weak acid, weak acid pH level will be closer to 7 than the strong acid. Weak acid does not dissociate completely, therefore a weaker proton donor, thus higher pKa. Strong acids dissociates completely and release all of their hydrogen atom when dissolve in water.
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The area where the blast originates is referred to as <span>Scene Perimeter/Isolation Zone. This whole area is dangerous for people since it can contain harmful gasses or falling debris depending on the environment of the blast.
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