At 10:10 AM +0000 11/9/99, Paul Richardson wrote:
"Just checking John, but bearing in mind the large quantities of acid and
water we're using is it pouring acid into water or water into acid that
causes the explosion??"... As I've forgotten the procedure, my question to
any chemists on the FOT list is, is there a hard and fast rule with the
safe mixing of water with all acids?
The general rule is to add acid to water. Acid dilution is (for the most
part) an exothermic reaction, meaning it gives off heat. Sulfuric acid
dilution is STRONGLY exothermic and adding water to concentrated acid
results in an explosion if the quantities are large enough. This is because
the water boils as it hits the acid. Any spattering that results from acid
into water will be water or very dilute acid. Hope this helps.
Phil Barnes (peb3@cornell.edu)
Cortland, NY (nowhere near New York City)
'71 TR6 CC61193L (22 year owner)
Someday we'll look back on all this and plow into a parked car.
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