Determining the Thickness of Zinc on a Piece of Galvanized Metal
DETERMINATION OF THE THICKNESS OF ZINC
ON A PIECE OF GALVANIZED METAL
Department of Biology, College of Science, University of the Philippines Baguio
ABSTRACT
The experiment was performed to be able to determine the thickness of zinc on a piece of galvanized metal. It also aimed for the students to be introduced to the reactivates of metals with acids as well as for them to develop some feeling for the size of an atom. In determining the thickness of the zinc coating on the metal, students, knowing the density of zinc, calculated the area (A) of the metal covered with zinc and the mass of zinc removed after it is reacted with HCL, hydrochloric acid. Given the radius of a zinc atom, on the other hand, students can also calculate the thickness of the zinc coating in terms of zinc atoms.
INTRODUCTION
Objectives
1. To determine the thickness of zinc on a piece of galvanized iron.
2. To properly calculate the thickness of the coating in terms of zinc atoms.
Galvanized metal is simply steel in some form that has received a thin coating of zinc oxide. The purpose of the zinc is to protect the steel from elements that normally would lead to oxidation, corrosion and the eventual weakening of the steel. In this sense, the zinc coating acts as what is called a sacrificial anode. In other words, the zinc will protect the steel from corrosion by acting as a barrier between the steel and the corrosive agent; at least until the zinc coating has been completely oxidized. Zinc plating involves the electrolytic application of zinc by immersing clean steel parts in a zinc salt solution and applying an electric current. This process applies a layer of pure zinc that ranges from a few microns on cheap hardware components to 15 microns or more on good quality fasteners. Technical and cost issues prevent the economical plating of components with heavier coatings. The service life of zinc coatings is a linear function of the zinc coating thickness. However, zinc
ON A PIECE OF GALVANIZED METAL
Department of Biology, College of Science, University of the Philippines Baguio
ABSTRACT
The experiment was performed to be able to determine the thickness of zinc on a piece of galvanized metal. It also aimed for the students to be introduced to the reactivates of metals with acids as well as for them to develop some feeling for the size of an atom. In determining the thickness of the zinc coating on the metal, students, knowing the density of zinc, calculated the area (A) of the metal covered with zinc and the mass of zinc removed after it is reacted with HCL, hydrochloric acid. Given the radius of a zinc atom, on the other hand, students can also calculate the thickness of the zinc coating in terms of zinc atoms.
INTRODUCTION
Objectives
1. To determine the thickness of zinc on a piece of galvanized iron.
2. To properly calculate the thickness of the coating in terms of zinc atoms.
Galvanized metal is simply steel in some form that has received a thin coating of zinc oxide. The purpose of the zinc is to protect the steel from elements that normally would lead to oxidation, corrosion and the eventual weakening of the steel. In this sense, the zinc coating acts as what is called a sacrificial anode. In other words, the zinc will protect the steel from corrosion by acting as a barrier between the steel and the corrosive agent; at least until the zinc coating has been completely oxidized. Zinc plating involves the electrolytic application of zinc by immersing clean steel parts in a zinc salt solution and applying an electric current. This process applies a layer of pure zinc that ranges from a few microns on cheap hardware components to 15 microns or more on good quality fasteners. Technical and cost issues prevent the economical plating of components with heavier coatings. The service life of zinc coatings is a linear function of the zinc coating thickness. However, zinc
Cited: Vallejo, V. L. (2006).General Inorganic Chemistry Laboratory Manual and Teacher’s Guide. UP Baguio. Determination of the Thickness of Zinc on a Piece of Galvanized Metal. Retrieved on December 12, 2013 from http://www.hschem.org/Laboratory/WoodrowWilsonFoundLabs/thicknessofzinc.htm Galvanized Coatings - Zinc Galvanizing versus Zinc Plating Galvanized Metal Lab. Retrieved on December 12, 2013 from http://www.materialseducation.org/educators/new/2007/docs/17-Acker.pdf What is Galvanized Metal? Retrieved on December 11, 2013 from