Thickness of Al foil

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Calculating the Thickness of Aluminum Foil

Background

In science, we make use of large and small numbers much of the time. In addition, we must often make use of one set of measurements, and known properties (such as density) to indirectly measure other quantities. One example of the type of measurement will be found in this experiment. The laboratory tools normally available would not be suitable for the direct measurement of the thickness of a piece of aluminum foil.

The formulas that will enable you to find the thickness of the foil are as follows.

V = L x W x H (V = volume, L = length, W = width, H = height)

A = L x W (A = area, L = length, W= width)

In the case of aluminum foil, we will substitute T (thickness) for H (height).

V = L x W x T

And, with a little manipulation, V = A x T

Solving for thickness:

T = V/A

The first problem will be to find the density of aluminum. Remember that the density is an intensive property that is expressed as

D = m/V.

The density of aluminum will be found by measuring the volume and mass of an aluminum cylinder. Use water displacement for the volume determination.

V = m/D

Next you will determine the mass, length and width of piece of aluminum foil that is approximately 10 cm square.

Objectives

1. Correctly use exponential notation in expressing the results of the thickness calculation.

2. Careful measurement using uncertainty.

Data

Read the procedure carefully and set up a data table.

· Use a ruler to make it neat.

· Label each column and row carefully.

· UNITS on all measurements!

Analysis

Determine the thickness of aluminum foil

SHOW ALL YOUR WORK AND BOX YOUR ANSWER.

Don’t forget about units!

Conclusion

The accepted thickness of the foil, which was printed on the box it came in, is recorded on the board. Calculate your percent error for the thickness of each piece of aluminum foil. Show your work and label the heavy duty and regular.

Test your understanding, answer the following.

A very thin layer of gold plating was placed on a metal tray that measured 25.22 cm X 13.22 cm. The gold plating increased the mass of the plate by 0.01512 g. Calculate the thickness of the plating. The density of gold is 19.32 g/cm3. Show your work!