Empire Of Electricity Lab Report

Name: Amra Aliyu

Lab partner: Jamie Liang

Lab: Empire of Electricity

Course: Chem 106

Date: 7/11/2015

INTRODUCTION

A galvanic cell is an electrochemical cell that goes through a redox reaction and

produces electrical energy . It converts chemical energy to electrical energy and the energy goes

from the anode to the cathode. In this lab we had manipulate an exothermic zinc reaction to

produce electricity. The same process is used in the making of commercial batteries. A more

detailed information about the procedure can be found in Cornerstone chemistry lab for Hunter

college chemistry 106 students.

DESCRIPTION OF SUBSTANCE

Zinc metal - grey silver solid

Zinc nails- grey solid

1.0M Zinc sulfate - blue liquid

Copper metal

For the first beaker we added 15 mL of 1M zinc sulfate into a clean medium beaker. At first we added the 15 mL of zinc sulfate into a large beaker, but when we inserted the salt bridge, we noticed that the salt bridge was not long enough to reach the 15 mL of solution in both large beakers. For the second medium beaker we added 15 mL of 1M copper sulfate. After both beakers were filled with 15 mL of the given solutions, we then placed the u-shaped salt bridge into the beaker, with one end of the salt bridge in the zinc solution and the other end in the copper solution. We had to make sure that the salt bridge was set up properly, so before inserting the salt bridge in the beakers, we added 0.2M potassium nitrate into the salt bridge, but were careful not to overflow the solution. My partner then inserted small pieces of cotton to plug both openings of the salt bridge. When we flipped the salt bridge over we noticed a small air bubble, to remove the air bubble we unplugged one of the openings of the salt bridge and added more potassium nitrate, and then reinserted the cotton.

Once we were confident that the salt bridge contained no air bubbles, we proceeded with placing a long thin rectangular zinc metal strip attached to an alligator clip in the zinc solution (not fully submerged). We also placed a copper strip of nearly identical size attached with an alligator clip into the copper solution. Both

We didn’t notice anything during setup 1 because we expected to get a reading of 0 V for the first setup, which even though was due to a faulty voltmeter actually ended up being the voltage reading for most groups in the class. The initial voltmeter that we were given seemed to be functional, and we even tested the voltage on a common battery. Upon using the voltmeter to test the voltage for setup 2, we had a voltage of 0. After switching alligator clips and switching the wires connected to the voltmeter, we still had a voltage of 0. After asking other groups of their voltage number for setup 2, we came to the conclusion of a faulty voltmeter. As a result, we switched voltmeters and after getting a different voltmeter and running the voltage again, did we come up with a voltage of 1.07 V. We discussed our findings with other groups and they seemed to be within our voltage range. However, the uncertainty that we encountered leads back to the accepted standard voltage (E knot) of 1.0-1.1 V. Our voltage range is a bit lower, but this uncertainty can be attributed to the lack of proper functioning voltmeters. Even though our second voltmeter seemed to be functioning properly, we can assume, based on my groups’ failure with our first voltmeter, that the other voltmeters weren’t functioning properly and can give a reading that is higher than what is expected. Despite our assertions, we are