CHEM 181 Lecture 7: Topic 3lesson 2

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amaranthtiger876

12 Feb 2019

School

McGill University

Department

Chemistry

Course

CHEM 181

Professor

David Noble Harpp, Ariel Fenster, Joseph A Schwarcz

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CHEM 181 verified notes

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CHEM 181 Lecture Notes - Lecture 6: Yolk, Canthaxanthin, Food Coloring

CHEM 181 Lecture 7: Topic 3lesson 2

CHEM 181 Lecture 8: Lecture 8 - Topic 2

Document Summary

Give you an idea of the wide spectrum of minerals that are, in fact, required in the diet. Phosphorus is important also for teeth and bones, the phosphate group. And then we have these other elements, namely vanadium (v) , molybdenum (mo), and tin (sn). It sounds like we might be making a car or something out of these, but we need these. And we"ll talk about one of them, namely molybdenum in a little bit of detail. These are the micronutrients as we have already described. And the total amount that is involved for a daily requirement would be a gram to a little more than a gram, but the gram is generally the amount of calcium that we would need. ~1-1 g/day all the rest, the slightly more than one gram amount to all the rest of the minerals that we"re dealing with.

Related Questions

Geoguay: "So how much of that super chunk chocolate is scoop of your super chunk chocolate ice cream?" Geogal "Well, in order to tell you I need to take a scoop of the ice cream and drop it on this weighing scale (splat), weigh it. pick out all those chocolate chunks and drop them on another weighing scale (thud), then take the weight of the chunks and divide by the weight of the scoop, multiply by 100 and there you have it: an eye-popping 42 percent (by weight) of super chunk chocolate in my super chunk chocolate ice cream" In lecture we talked about the importance of mineral resources in sustaining our society and that every American consumes about 9 kilograms, or 20 pounds, ofeopper per year. That figure is based on an estimate of the national demand for copper to make such things as electrical wire, tubing, and electronic components (to name just a few) divided by the US. population. Like other metals, the copper you use comes from minerals, which in turn are extracted from earth's crust. Remember from lecture that valuable minerals do not occur in large pockets of pure, solid masses but are widely dispersed throughout earth's crust and mined where geological processes have enriched their concentration. This homework problem will help you appreciate the value of metal in minerals and the volume of rock material that must be processed to meet your annual demand for copper. Back A common "ore" of copper is the mineral chalcopyrite. Chalcopyrite is often the principal ore mineral in "porphyry copper deposits" as presented in class. You have analyzed the physical properties of chalcopyrite in laboratory so you already know some things about it or where to go to refresh your memory. Chalcopyriteis a sulfide mineral so this means it contains more than just copper. In addition to sulfur (S), chalcopyrite contains some iron (Fe) and the proportions of these metals in the mineral are expressed by its chemical formula: CuFeS2. So how much copper (Cu), say by weight percent, is in chalcopyrite? Let's use another copper sulfide mineral as an example ofhow this calculation is made. How much copper is in the mineral chalcocite? Chalcocite is another ore mineral of copper. In order to determine this one needs to know the chemical formula and atomic hts of the included chemical elements. The chemical formula for chalcocite is Cu:S The atomic weight of the chemical elements C and S are 63.55 and 32.07, respectively (this info can be retrieved from a Periodic Ta of the Elements like the one lecture. This means that the chemical formula weight ofchalcocite i 2x63,55 (Cua) 32.07 (S) 159.17 grams (CuzS) and the weight percent of Cu in chalcocite is 127.10 (Cu) divided by 159.17 (Cu2S) x 100 79.85%

in part A the mass of empty tray was 2.78g
and the mass of tray with stopper was 38.82
the mass of the stopper is 38.82_2.78=36.04
we repeat this thing again with second type of observation and we get 39.2678_2.6409=36.6269
and the we did find the average
in part D we cut the glass and we use the bunse burner to make it smooth that was about 15 min
in Part E when the water was boiling poiling chips were moving a lot and there was so much steam
and then the sodium chloride became powder and a little bit salt
in part F when we mix the sodium iodid and the lead nitrate the mixture became yellow and when we did the filtration the yellow stay on the filter paper but all the water came down
plzzz i need three paragraphs conculsion and i need the answers for the last pictures

What would be the independent, dependent, and controlled(need 3 controlled variable) variables in this lab?

- what would be a good hypothesis?

- for the second reaction, my teacher told us to change something in the lab and see how much gas forms after that, what would be something that we should change?