The Foundations of Chemistry

18 Ionic Equilibria I: Acids and Bases ...

OUTLINE 18-1 A Review of Strong Electrolytes 18-2 The Autoionization of Water 18-3 The pH and pOH Scales 18-4 Ionization Constan ...

A REVIEW OF STRONG ELECTROLYTES In previous discussions we have seen that water-soluble compounds may be classified as either el ...

The formation of an H 3 O
ion by the ionization of water is always accompanied by the formation of an OHion. Thus, in purewater ...

Because the product (0.050
x)(x) is a very small number, we know that xmust be very small. Thus, it will not matter whether we a ...

Note that we use pH rather than pH 3 O. At the time the pH concept was developed, H 3 O
was represented as H
. Various “p” term ...

Solution From the definition of pH, we write log [H 3 O
]3.301 Multiplying through by 1 gives log [H 3 O
]3.301 Taking the ...

EXAMPLE 18-5 Calculations Involving pH and pOH Calculate [H 3 O
], pH, [OH], and pOH for a 0.015 MHNO 3 solution. Plan We write ...

EXAMPLE 18-6 Calculations Involving pH and pOH Calculate [H 3 O
], pH, [OH], and pOH for a 0.015 MCa(OH) 2 solution. Plan We wr ...

In the indicator method we prepare a series of solutions of known pH (standard solu- tions). We add a universal indicator to eac ...

Let us consider the reaction that occurs when a weak acid, such as acetic acid, is dissolved in water. The equation for the ioni ...

A dilute solution of nicotinic acid was found to contain the following concentrations at equi- librium at 25°C. What is the valu ...

EXAMPLE 18-9 Calculation of Kafrom pH The pH of a 0.115 Msolution of chloroacetic acid, ClCH 2 COOH, is measured to be 1.92. Cal ...

Because ionization constants are equilibrium constants for ionization reactions, their values indicate the extents to which weak ...

Substituting these algebraic representations into the Kaexpression gives Ka3.5 10 ^8 This is a quadratic equation, but it i ...

From our calculations we can draw some conclusions. In a solution containing only a weak monoprotic acid, the concentration of H ...

This gives [CH 3 COOH]ionizedx1.3 10 ^3 M. Now we can calculate the percent ioniza- tion for 0.10 MCH 3 COOH solution. % ion ...

From Example 18-12, we see that the stronger acid (HF in this case) has the larger Ka value and the smaller pKavalue. Conversely ...

Thus far we have focused our attention on acids. Very few common weak bases are soluble in water. Aqueous ammonia is the most fr ...

Solution The equation for the ionization of aqueous ammonia and the algebraic representations of equi- librium concentrations fo ...