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Please help me with some chemistry, ns!
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it told me at the bottom of my window that an error had occured while trying to load the document...
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link says AP, which is way out of my league...i thought id try anyway
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^^alright ill put it directly on this forum.
^this is 12th grade ap chem.
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1.from the information below, determine the mass of substance C that will be formed if 45 grams of substance A reacts with 23 grams of substance B. assume that the reaction between A and B goes to completion.
substance A is a grey solid that consists of and alkaline earth metal and carbon(37.5% by mass. it reacts with substance B to form substances C and D. Forty million trillion formula units of A have a mass of 4.26 milligrams
47.9 grams of substance B contains 5.36 grams of hydrogen and 42.5 grams of oxygen
when 10 grams of substance C is burned in excess oxygen, 33.8 grams of carbon dioxide and 6.42 grams of water are produced
substance D is a hydroxide of the metal in substance A
2.A naturally occurring pigment contains only carbon, hydrogen, and oxygen. It was commonly used as a dye in the first half of the nineteenth century. it is 53.66% C and 4.09% H by mass. a titration requires 18.02 mL of .0406 M NaOH to .3602 grams of the pigment. assuming one acidic hydrogen per molecule, what it the molecular formula of this pigment?
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you are going to need the specific known values for molecular weight, etc. from the tables in the appendix of your textbook. do you guys use the book written by zumdahl? also, those are called marathon problems for a reason. they have a ton of steps with lots of busy work, math, and basically you will need to look through your periodic table for the elements that have the same weights and whatnot as the value you find with your calculations. we could probably still get them right, but the surefire way is to have the same source material as you, because the values differ slightly in each publication.
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holy shit, i cant remember any of that stuff, damn...im only a sophomore in AP bio, i did titration whatever last year aaaahhhh...im sure if i had time id work it out but wow...its missing little bits and pieces of info that i cant figure out how to find
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reaction Stoichiometry blows.
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I'm taking that AP chem also. Those will literally take you hours to do, so I'll bring the problems in to my teacher, have him give me the answers, and get back to you.
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i would love you, but i have to have work that explains my answers as well. the answers will definitely help and now i think i have a general direction in which to go.
this isn't due until the 16th, too, so i still have some time.
thanks for the responses.
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you need to use the atomic mass with the percentages and that is all i know. and alkalai earth metals are like group 2 or sumthing
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im guessing no one likes chemistry enough to do it for fun
shucks.
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My best guess for the second one is Indian Yellow. I tried a bunch of pigments on wikipedia, and thats the one that fits those ratio's the best.
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shit its amazing how quickly you forget stuff, I was doing stuff like that in chem 2 years ago but haven't done any since and can't even remember where to start
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ive figured out the first one, i think its right.
the second is still a mystery, ill look into that indian yellow
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this just in. i'm one of three people in my AP class that is passing.
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hahahaha my brain is fried just looking at that
i guess that's why im getting my last college science hours in "caveman chemistry"
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god dude thats tough. your in too smart of a class
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