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Lecture: The Mole & The Great American Hardware Store

The buck stops here.

There are a few concepts in chemistry and economics that are so important that you cannot go forward with any hope of success unless they are understood. In fact today’s lesson on the “mole” or molecular weights is of such significance that you not only have to understand, but it must become so well ingrained in your mind that you don’t even think about it when doing your chemistry homework or tests. It must become just part of your nature, something so well understood that its like walking and texting at the same time. No one can get a grade in this course above say a D- without this achievement. The economics part of todays lesson is a bonus that will help you in understanding the material world you and I live in and keep you from thinking that getting and keeping a good job just happens.

Now, I want you to forget about what I have just talked about and concentrate on a story about the “Great American Hardware Supply Company. In this story you are a group of the employees and today you have been called into a meeting with the general manager (that would be me) to talk about some changes that are going to be made starting today. The company has not been making much of a profit  over the past many months and the board of directors are willing to keep the doors open for one more effort to turn things around. We have tried raising our prices, but sales go down and our balance sheet stays the same. The term for this is that our products demand versus price is elastic. We are a middle man operation. We buy hardware items   (nuts, bolts, washers, pins, cotter keys, thumb screws, etc.) in large amounts (truck loads) and sell them to hardware stores in shelf display amounts. We have a sales staff that visits thousands of hardware stores each month in 22 states and our job, in this warehouse operation, is to fill those orders and UPS the items to the stores. We need to do this efficiently and accurately. The board has agreed to ask the investors to stick with us in this last effort to turn things around.  This last effort is centered around cutting our order fillers from thirty down to approximately ten.  A single employee cost us wages, medical insurance, dental insurance, vacation pay, sick leave, retirement fund matching and more which adds up to over $75,000.00 per year. Even so some employees come in late or miss work completely due to snow storms, car trouble, missed busses, sick family members, sick friend, sick dog, and god only knows what else (each year I would read from a list that I kept from the start of school for why students missed class). Management blames your union for much of this expense, but going through a strike in an effort to change your contract at this time would be costly and most likely put us out of business. If ten can do the work of thirty we save a million and a half dollars per year. That’s enough for the remaining employees to be given a small raise and to allow our stock holders to get a reasonable return on their investments.

For ten to do the work of thirty we need a new approach to filling orders. The current counting method has been accurate, but is too slow requiring thirty employees to keep up with orders.  From now on anyone caught counting anything for any reason will be let go. The new method is a weight based system using the following table. On the “The Periodic Table of Hardware Elements” each hardware item we sell is displayed along with the bin number and that items dozen weight. Those of you that can handle the concept, do the math in the prescribed manner, work the scales properly and do all this proficiently will be invited to take a test. Those with the top 15 scores will be able to continue their employ with the company. After two months the top ten in proficiency and accuracy will be offered a raise and what should be long term employment. If this works to the point where we can undersell competitors we will be able to expand. If so, we would be looking for some of you that were laid off, but proved you could do the work under the new process, to be hired back. What we are hoping is that our investment in fifteen portable electronic scales (a one time cost with a predictable up-keep contract that won’t be late for work etc. etc.) we can do the work of thirty with just the ten.

Starting today our sales staff will be sending in all orders by the dozen. We are going to think by the dozen, talk by the dozen, walk by the dozen, eat by the dozen, live by the dozen and if need be The Great American Hardware Supply Company will profit or die by using the dozen concept.

When you fill an order you will do a bit of math in the following prescribed manner and weigh out the items. Please let me emphasize that you will be weighing out the order and not counting. This is not complicated if you will recall the concept of a unit factor from your high school math education. Our order checker will want to see your worksheets and each item on an order filled must be calculated and shown in the following prescribed manner.

Keep in mind that we also get returns and that it is your responsibility to count the items returned by weight and report it out in dozens. Our customers expect and deserve proper credit applied to their accounts so this must be done accurately. I’m going to leave it to you to come up with the process for a weight based dozen determination of a return. Please set it up as above so the our checker will be able to efficiently review your work.

We have many hardware complexes that are put together for use on manufacturing assembly lines of companies like Toro, GE, GM, etc. We will continue our practice of hiring temporary college students in the summer to put the complexes together as your union contract allows. These temps are hired at minimum wage with no benefits keeping the dozen cost of assembly appropriately low. The complexes will not appear on the Periodic Table of Hardware Elements. Again I leave it to you to come up with a method of filling such orders based on the dozen concept along with using weight as the counting method. Also use the same unit factor method of displaying your work to maintain checking speed.

Last, we have some bins of complexes that have been discontinued and will be taken apart and placed back into the general inventory. Keeping our inventory count accurate is important so as to have product on hand to fill orders and not create backorders. I again will leave it to you to develop a method of determining the inventory increase of each element in the process of taking a bin of complexes apart. Of course our minimum wage college students will do the work. Keep in mind that inventory is now all stated by how many dozen of each element we have on hand.

Please note that even though we all know how many items are in a dozen that for all the work you are being asked to do you will never actually use the number twelve. It’s not that the number twelve is meaningless it’s just that if you walk, think, talk, order, live, etc. by the dozen the dozen becomes the unit of doing business and the number of items in that dozen becomes almost irrelevant. If we were dealing with much larger numbers in the average order it might have been better to use the “gross” (144 things) as our base unit. Or maybe we could go really crazy and be like the chemist and call the dozen a “mole” (6.02 X 1023 things) and use that as our unit to walk, talk, think, and figure by.

I think that introducing problems where you would actually use the 6.02 X 1023

during the introduction of the mole concept is not a good idea. Later I would ask if an engineer were to write and want to know how much a single hardware element or  complex would weigh how would we go about determining that value without going out and getting one and weighing it. Students will do that without much difficulty and are not baffled by the hard to comprehend number. After some time to get used to the idea of the mole as just the chemist dozen it’s not hard to add in the seldom used huge number representing the number of things in a mole.