Which compounds are the brønsted lowry bases in this equilibrium

In the reaction between NH 3 and H 2 O,. At this point, we say the chemical reaction is at equilibrium. Both processes still occur, but any net change by one process is countered by the same net change of the other process; it is a dynamic , rather than a static , equilibrium.

Because both reactions are occurring, it makes sense to use a double arrow instead of a single arrow:. What do you notice about the reverse reaction? If you consider the species in this chemical reaction, two sets of similar species exist on both sides. These sets are marked here:. These sets are marked here:. Many household products are acids or bases. For example, the owner of a swimming pool may use muriatic acid to clean the pool.

Muriatic acid is another name for HCl aq. In a medicine chest, one may find a bottle of vitamin C tablets; the chemical name of vitamin C is ascorbic acid HC 6 H 7 O 6. One of the more familiar household bases is NH 3 , which is found in numerous cleaning products.

This is one explanation for why soap solutions are slippery. Perhaps the most dangerous household chemical is the lye-based drain cleaner. Lye is an extremely caustic chemical that can react with grease, hair, food particles, and other substances that may build up and clog a water pipe. In this theory, acids are defined as proton donors; whereas bases are defined as proton acceptors. For example , consider the following chemical equation:.

In this theory, an acid is a substance that can release a proton like in the Arrhenius theory and a base is a substance that can accept a proton. In the case of the HOH it is a base in the first case and an acid in the second case. The hydroxide ion in these compounds accepts a proton from acids to form water:. We call the product that remains after an acid donates a proton the conjugate base of the acid.

This species is a base because it can accept a proton to re-form the acid :. This species is an acid because it can give up a proton and thus re-form the base :. In these two sets of equations, the behaviors of acids as proton donors and bases as proton acceptors are represented in isolation. In reality, all acid-base reactions involve the transfer of protons between acids and bases. For example, consider the acid-base reaction that takes place when ammonia is dissolved in water.

For example, when hydrogen fluoride dissolves in water and ionizes, protons are transferred from hydrogen fluoride molecules to water molecules, yielding hydronium ions and fluoride ions:. When we add a base to water, a base ionization reaction occurs in which protons are transferred from water molecules to base molecules. For example, adding pyridine to water yields hydroxide ions and pyridinium ions:.

Notice that both these ionization reactions are represented as equilibrium processes. The relative extent to which these acid and base ionization reactions proceed is an important topic treated in a later section of this chapter. In the preceding paragraphs we saw that water can function as either an acid or a base, depending on the nature of the solute dissolved in it.