8.2 Electrolytes and Nonelectrolytes General, Organic, and Biological Chemistry Fourth Edition Karen Timberlake Chapter 8 Solutions 8.2 Electrolytes and Nonelectrolytes Lectures © 2013 Pearson Education, Inc.

Electrolytes, Nonelectrolytes In water, strong electrolytes separate into ions making solutions that conduct electricity. weak electrolytes produce a few ions. nonelectrolytes produce molecules, not ions.

Strong Electrolytes Solutes that are strong electrolytes dissociate 100% or break up into positive and negative ions in water. form aqueous solutions (aq) when dissolved in water that will conduct an electrical current. H2O 100% ions NaCl(s) Na+(aq) + Cl(aq) H2O CaBr2(s) Ca2+(aq) + 2Br(aq)

Learning Check Complete each of the following equations for strong electrolytes dissolving in water.

Solution Complete each of the following equations for strong electrolytes dissolving in water.

Weak Electrolytes Solutes that are weak electrolytes dissolve in water mostly as molecules. dissolve in water forming a few ions. produce solutions that conduct electricity weakly.

Nonelectrolytes Solutes that are nonelectrolytes dissolve as molecules in water. do not produce ions in water. form solutions that do not conduct an electrical current.

Classification of Solutes in Aqueous Solutions

Equivalents An equivalent (Eq) is the amount of that ion equal to 1 mole of positive or negative electrical charge (+ or –). For example, 1 mole of Na+ ions and 1 mole of Cl− ions are each 1 equivalent or 1000 milliequivalents (mEq) because they each contain 1 mole of charge, and ions with a charge of 2+ or 2−, contain 2 equivalents for each mole. 1 mole Na+ = 1 Eq 1 mole Ca2+ = 2 Eq 1 mole S2− = 2 Eq

Equivalents of Electrolytes

Electrolytes in Body Fluids Electrolytes play an important role in maintaining the proper function of the cells and organs in the body. Sodium ions regulate water content and carry electrical impulses through the nervous system. Potassium ions are involved in the transmission of electrical impulses and help maintain a regular heartbeat. Bicarbonate ions help maintain blood pH.

Electrolytes in Blood Plasma

Learning Check 1. In 1 mole of Fe3+, there are A. 1 Eq. B. 2 Eq. C. 3 Eq. 2. In 2.5 mole of SO42−, there are A. 2.5 Eq. B. 5.0 Eq. C. 1.0 Eq. 3. An intravenous bottle contains only NaCl. If the Na+ ion produces 34 mEq/L, the Cl− ion produces A. 34 mEq/L. B. 0 mEq/L. C. 68 mEq/L.

Solution 1. In 1 mole of Fe3+, there are 3 equivalents (Eq). C. 3 Eq 2. In 2.5 mole of SO42−, there are 5 equivalents. B. 5.0 Eq 3. An intravenous bottle contains only NaCl. If the Na+ ion produces 34 mEq/L, the Cl− ion produces A. 34 mEq/L.