Double displacement reaction water producing

Neutralization reactions are a special type of double displacement reaction that produces water. Neutralization involves the reaction of an acid with a base to form water and an ionic compound. You will learn more about neutralization reactions in Chapter 10. For example, the neutralization of hydrogen nitrate (nitric acid) with sodium hydroxide (a base) is a double displacement reaction. 

Double Displacement Reactions That Produce Water... 

Acid-base reactions are a special type of double displacement reaction. Acid-base reactions occur when an acid and a base react with one another. An acid is a compound that contains hydrogen and gives off hydrogen ions (H+) when it is dissolved in water. Bases, on the other hand, produce hydroxide ions (OH ) when they are dissolved in water. 

Acid-base reactions (neutralization). An acid, which contributes H+ (H30+) ions, and a base, which contributes OH- ions, undergo metathesis to produce water (HOH or H2O) and a salt. Isn t this a special case of a double displacement reaction ... 

In certain cases, you know that a double displacement reaction has occurred because a gas is produced. The gas is formed when one of the products of the double displacement reaction decomposes to give water and a gas. 

A gas can also be produced indirectly. Some unstable compounds formed in a double-displacement reaction, such as H2CO3, H2SO3, and NH4OH, will decompose to form water and a gas ... 

The double-displacement mechanism with its covalent intermediate can often be distinguished from single displacement reactions by kinetic experiments in which an appropriate nudeophilic spedes is added to reaction solutions of enzyme and substrate and allowed to compete with water for the covalent intermediate. The dependence of initial velocity on the concentrations of substrate and added nucleophile will produce a distinctive kinetic pattern (i.e., ping-pong kinetics). Observation of such a pattern constitutes strong evidence suggesting that the hydrolase under study effects catalysis through a double-displacement mechanism. 

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