### Introduction

Acids react with metals. For example, hydrochloric acid reacts with zinc metal according to the equation

${\text{Zn(s) + 2 HCl(aq)}} \to {{\text{H}}_{\text{2}}}{\text{(g) + ZnC}}{{\text{l}}_{\text{2}}}{\text{(aq)}}$

Strong acids react faster and more vigorously with metals than do weak acids. Because water solutions of acids contain ions, these solutions conduct electricity. The measure of electrical conductivity is related to the number of ions in solution. Conductivity units are microsiemens per centimeter (μS/cm).

### Objectives

In this experiment, you will

• React zinc metal with various acids.
• Measure electrical conductivity.
• Investigate the relationships among acid strength, electrical conductivity, degree of ionization, and chemical activity.