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We're heading back to Breaking Bad. One of the most
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memorable scenes in Breaking Bad involved Jesse Pinkman, a bathtub,
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and a spectacular misunderstanding of chemistry. Walter Wright has instructed
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Jesse to use hydrofluoric acid to dispose of a body.
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Jesse ignores the warning about choosing an appropriate container and
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uses an upstairs bathroom instead, or bathtub. Later, the ceiling collapses,
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sending a grotesque mixture of debris and biological material crashing
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into the hallway below. It's horrifying, dark, comedic, and apparently
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a demonstration of hydrofluoric acid's incredible power. But how much
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of it is actually true or scientifically accurate? First, hydrofluoric
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acid is a generally dangerous chemical. However, the danger comes
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from some unusual properties that distinguish it from more familiar acids.
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Most people associate the acid's strength with how aggressively a
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substance damages tissue. But in chemistry, acid strength describes how
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readily an acid releases hydrogen ions in solutions. Hydrofluoric acid
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is technically classified as a weak acid because it is
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not completely disassociated in water. Now, it doesn't make it
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safe either. Unlike many other corrosive substances, hydrofluoric acid can
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penetrate deeply into tissue. Fluoride ions can interfere with essential
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biological processes, including those involving calcium and magnesium. This can
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produce several local injuries and serious exposures, potentially fatal disturbances.
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A person exposed to hydrofluoric acid may initially experience surprisingly
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little pain depending on the concentration and circumstances. What about
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dissolving an entire human body? Human tissue is not a
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uniform substance. It contains water, proteins, lipids, connective tissue, and
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mineralized structures such as bones and teeth. Different chemicals interact
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with these components in different ways. Hydrofluoric acid can cause
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severe cancer. tissue destruction, but the rapid, nearly complete disappearance
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of a body is not a realistic representation of the
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chemical behavior. How about the matter of the bathtub? Hydrofluoric
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acid is famous for attacking glass and certain silica-containing materials.
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This is one reason it requires specialized handling in industrial
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and lab environments. However, a household bathtub is not necessarily
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made from the same materials as lab glass. Bathtubs may
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contain acrylic, fiberglass composites, porcelain, or other materials. The show's
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dramatic destruction of the bathtub and supporting floor, therefore, cannot
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be explained simply by saying that hydrofluoric acid dissolves everything.
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The chemical is highly selective in its reactions, and that's
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what makes this scene such an interesting example of Hollywood chemistry.
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The writers correctly identified a substance with unusually dangerous toxicological properties,
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but exaggerated the ability to rapidly destroy large amounts of
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biological and structural material. There are also limitations to evaluating
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the scene. The fictional chemical concentration, exposure, and construction materials
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are not established precisely enough to reconstruct the event. The
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broader scientific conclusion is clear, though. Hydrofluoric acid is very,
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very hazardous, but not because it behaves like a universal
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solvent capable of dissolving everything. Its most frightening properties involve
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its ability to penetrate tissue and disrupt essential biochemical processes.
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The real chemistry could be more disturbing than the fictions.