Any Chemistry people?

shouldn't take as much then

 

Go to Khan Academy.

I thought we would shit on threads where people ask for help on homework or anything school related..

 

If you need a way to check your own work, try this

http://www.wolframalpha.com/

it will give answers to a lot of stuff, you just have to figure out how to phrase it

I check all my calc homework and a lot of my chemistry homework with it

 

SWEET .... LMAO I learned what chemicals not to mix with HCL's

 

Well put that in your notes til you get to college

 

Hahaha it's not just cause I'm 16, it's cause I'm 16 and weigh 125 lbs.....

 

Keep posting (or PM) if you have specific questions. I'm going to be AFK for a couple of hours but I'll check back.

If you need more practice equations (I strongly recommend it--you should try to crutch yourself along, using guides only as needed until you can do half a dozen without any crutches), I can post some up. Then use the equation balancer I posted earlier to check your work. If you can do a bunch without using the balancer until you're finished, and they come out correct, you're in good shape.

The more of these you see and try, the more you'll get comfortable with what to expect and what the pitfalls are (like complex ions such as PO4 and NO3, and using H2O to fill in voids in the product side). Keep at it--you can do it!

 

I can try to answer them too, depending on what the question is

 

oh well then you'll have it done in two shots. . .ah. . i mean minutes.

 

OP, I guess you put this in the right section inadvertently It seems you are going into your test unprepared, prayers to you that this isn't what you hear tomorrow following your test.

http://www.youtube.com/watch?v=5hfYJsQAhl0

 

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Chemistry was my worst subject in college (my only C) ... especially organic chemistry ...
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holy crap all this nonsense just blew my mind!!! god how i failed chemistry and geometry miserably, but luckily had a coach as a teacher so i somehow always managed to get a "70". thank god. hehe

 

I actually understand it now,6 out of 7 questions I tried on my own, I got right. Definitely will be going into this test more confidant than I was, thanks again everyone!

 

good luck, if you need to check your work, wolfram alpha will be able to help you if no one is on etc....

 

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Opps .. posted this one in wrong thread ... moved to "WTF Thread ...

 

Ugh, I'm in Organic right now. Hell...No better word for it.

 

That's good news.

Let us know how it goes, and don't be afraid to ask for help on the next section (before the night before the test would be best )

 

Haha will do and I had actually been reviewing the material the past 3 days, just still didnt understand so I've been asking everyone possible.

 

I believe I'm gonna have to take you up on this. Ive been working problems for about 2 hours and I still have no idea...this chapter is stoichiometry. A couple questions:

Metallic copper is formed when aluminum reacts with copper(II) sulfate. How many grams of metallic copper can be obtained when 54.0g of Al react with 319g of CuSO4?
Al+3CuSO4--->Al2(SO4)3 + 3Cu


If 8.6L of H2 reacted with 4.3L of O2 at STP, what is the volume of the gaseous water collected?
2H2 + O2----> 2H2O


How many liters of O2 are needed to react completely with 45.0L of H2S at STP?
2H2S + 3O2-----> 2SO2 + 2H2O


If anyone can explain to me what to do and why you are doing it I would greatly appreciate it!

 

your gonna need a periodic table for stoichiometry. you are also going to need to find the limiting reactant. hopefully somebody can make it clear how to do that because i am not great at it. once you find that you do this.

take the initial mass of whatever you are starting with. for example, you have 54.0g of Al. you then need to find the molar mass or how much 1 mole of Al weighs(the number usually underneath of Al on the periodic table) then you take the number of moles you start with which in this case is 1 which you know from the equation. then you take the number of moles of Cu that will be made in this case 3 and you also need the molar mass of Cu. now once you know all that set it up like this

initial mass(g)*(number of mol of reactant/molar mass reactant(g))*( number of mol of product/number of mol of reactant)*(molar mass of product(g))= total mass of product(g)

its hard to show on here but if you set it up so when you divide it is literally 1 over molar mass you will be able to see that units will cancel out and that is how you know you did it right. I don't want to give you the answer because it isnt really helping anyone if i do haha but let me know if you want me to clear anything up.