Electrical Conductivity: A Useful Property of Matter
Electrical conductivity is a property that describes the ability of a substance to transmit an electric
current. Substances that conduct electricity well have a high value for electrical conductivity.
Substances that don’t conduct electricity well have a high value for electrical resistivity, which is the
opposite of conductivity. In this experiment we will examine a variety substances to learn about their
ability to conduct electric current.
Part I: Classifying Substances - Identify each of the following substances as either and element or
a compound. For the substances that are elements, further identify them as either metals or non-
metals. For each substance, explain why you classified it the way you did.
Substance Symbol/Formula Classification Reason
Part II: Thinking from personal experience and prior knowledge - Answer the following
questions based on what you know from your own experience or previous learning.
1. Describe what you know or believe about the ability of metals and non-metals to conduct
2. You have always been cautioned not to take the hair dryer in the shower or bathtub. Why?
Part III: Making Predictions - For each substance in the table below, predict whether you think it
will conduct electricity or not, and the reason you think so. Use the terms “conductor” or “non-
Substance Prediction Reason
1. Look at the list of substances you think will conduct electricity. What do these substances have in
2. Look at the list of substances you thing will not conduct electricity. What do these substances
have in common?
Part IV: Testing Conductivity - Using a conductivity tester, test the conductivity of each of the
substances in the table below. Use the words yes or no to describe the conductivity of each
Substance Conductivity Substance Conductivity
Sugar Aluminum nitrate
Copper sulfate Ammonium sulfate
1. Now compare your conductivity predictions with your conductivity test result. List the substances
for which you predicted correctly, and the substances for which you predicted incorrectly.
2. What did you learn in this experiment about the ability of elements to conduct electricity? Write a
one-sentence statement that describes the conductivity of elements.
3. What did you learn in this experiment about the ability of compounds to conduct electricity?
Write a one-sentence statement that describes the conductivity of elements.
Part V: Further experiments with conductivity - In the following data tables, predict whether or
not you think the substances will conduct electricity, and the reason for your prediction. Then record
observations as Mr. Syron demonstrates the conductivity of each substance
Substance Prediction Reason Observations
Salt and water
Sugar and Water
Copper sulfate and
1. Compare the conductivity of plain salt and plain water with the conductivity of the salt and water
mixture. Offer your best explanation for the differences you see.
2. List and classify the elements in each of the compounds that conducted electricity when mixed
3. List and classify the elements in each of the compounds that did not conduct electricity when
mixed with water.
4. Compare your list of elements in question 2 with your list of elements in question 3. What
difference do you see between the two lists of elements? Propose a theory about how this difference
might affect electrical conductivity.