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\section{Chemistry}

Ex:
Soaps are essentially useless in acidic water, because in acidic water the carboxylate
ions of soap molecules pick up hydogen ions to form the undissociated fatty acid:

$$RCCO^- \quad + \quad H^+ \quad\longleftarrow\quad RCOOH$$

$$RCCO^- \quad + \quad H^+ \quad\longrightarrow\quad RCOOH$$

$$RCCO^- \quad + \quad H^+ \quad\longleftrightarrow\quad RCOOH$$

$$RCCO^- \quad + \quad H^+ \quad\Longleftarrow\quad RCOOH$$

$$RCCO^- \quad + \quad H^+ \quad\Longrightarrow\quad RCOOH$$

$$RCCO^- \quad + \quad H^+ \quad\Longleftrightarrow\quad RCOOH$$

$$RCCO^- \quad + \quad H^+ \quad\rightleftarrows\quad RCOOH$$

$$RCCO^- \quad + \quad H^+ \quad\leftleftarrows\quad RCOOH$$

$$RCCO^- \quad + \quad H^+ \quad\rightrightarrows\quad RCOOH$$

$$RCCO^- \quad + \quad H^+ \quad\leftrightarrows\quad RCOOH$$

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