i need some help on chemistry homework..

coolgirlspyer90

coolgirlspyer90

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I tried solving this for about an two and a half hours but i couldn't get it.

1) 2C2H6+702-> 4CO2+ 6H2O
A) How many moles O2 are needed to react with 7.0 mol C2H6?
B) How many moles CO2 are produced by the reaction of 9.0 mol O2?

2) 2C2H6+ &O2-> 4Co2+ 6H2O
A) How many moles (maximum) CO2 can be produced from 55.0g C2H6?
B) What mass O2 is needed to produce 85.0g H20?
C) What mass C2H6 is needed to produce 100.0G Co2?

3) Zinc minerals exist as smithsonite, ZnCo3, at Mining Site A and sphalerite, ZnS, At Mining Site B. Based only on percent composition of the minerals, at which site would mining of zinc be most feasible?

4)For each of the following equations, complete an atom inventory and indicate whether the equation is balanced:

A) Rb+ RbNO3-> Rb2O+ N2

____Rb____
____N____
____O____

B) HCL+ NaOH-> NaCl+ H2O

____H____
____Cl____
____Na____
____O____
____H____

5) A mole of carbon and a mole of hydrogen have different masses, but both represent 1.00 mol of substance. explain.


help is appreciated!! :ty::ty::ty::ty:
 
It's been awhile since I used chemistry, but do you know the basics of stoichiometry??

All of those questions you asked are stoichiometry.
 
sheila022 said:
It's been awhile since I used chemistry, but do you know the basics of stoichiometry??

All of those questions you asked are stoichiometry.
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nope, we haven't really gone over that yet. We're just going over like balanced chemical equations,Molar Masses, Molar Relationships, and a section C supplement from our text book. But my textbook didn't really help me as much. I looked through my notes and no help as well. So i tried going online to find some hints and clues. but nope. This packet is due tomorrow btw.
 
coolgirlspyer90 said:
nope, we haven't really gone over that yet. We're just going over like balanced chemical equations,Molar Masses, Molar Relationships, and a section C supplement from our text book. But my textbook didn't really help me as much. I looked through my notes and no help as well. So i tried going online to find some hints and clues. but nope. This packet is due tomorrow btw.
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Good ole stoichiometry I will give it a whirl but it will take me a minute to put it all together and its hard to explain over chat but I will try hang on
 
It is your fault that you didn't pay attention to your teacher.
 
ember said:
Good ole stoichiometry I will give it a whirl but it will take me a minute to put it all together and its hard to explain over chat but I will try hang on
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haha okay. my dad offered me to leave my homework out when he comes home from work at 3AM and try and answer some of my questions from my packet. But i didn't want him to do that because he has been sick and been really tired from work. he has a 4pm-3am pharmacist work shift at the hospital.
 
kevbo said:
It is your fault that you didn't pay attention to your teacher.
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I did pay attention to my teacher, My interpreter didn't sign everything in class. I asked my teacher for help, i always do. he clarified some things up, but i still need help. My interpreter wasn't there today, and my school didn't find a sub for me until the last minute.
 
coolgirlspyer90 said:
I did pay attention to my teacher, My interpreter didn't sign everything in class. I asked my teacher for help, i always do. he clarified some things up, but i still need help. My interpreter wasn't there today, and my school didn't find a sub for me until the last minute.
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I'm sorry but I have to be an asshole about this. You just don't go on line posting your homework. You will never learn from this. Get a tutor.
 
kevbo said:
I'm sorry but I have to be an asshole about this. You just don't go on line posting your homework. You will never learn from this. Get a tutor.
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I have no time for a tutor. I have band practice and competitions almost everyday, and i'm taking music lessons, and babysitting as well.
 
Hey how much of your study do you remember its been awhile but you use avagadros with moles and a mol to mol ratio right?
 
ember said:
Hey how much of your study do you remember its been awhile but you use avagadros with moles and a mol to mol ratio right?
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Yep, but my teacher showed us a different way of doing that instead of ratios. Here's an example of what he typed down on the packet:

Example 1: How many moles are present in 352 g of iron (III) oxide, Fe2O3?

Step 1: Caculate the molar mass of Iron (III) oxide
By adding the mass of two moles of iron atoms and three moles of oxygen atoms, the molar mass is calculated to be 160.0g.
This can be expressed in two ways as a conversion factor. It is either:
A) 160.0 g of Fe2O3 contains 1 mole (160.0g/1 mol) or
B) 1 mole of Fe2O3 contains 160 g (1 mol/160.0g)

Step 2) Arrange the molar mass so the original units cancel and the desired units are on top

352g Fe2O3 X 1 mol Fe2O3
____________= 2.20 mol Fe2O3
160.0g Fe2O3


Example 2: How many grams are present in 1.43 moles of magnesium hydroxide, Mg(OH)2?

Step 1: Caculate the molar mass of magnesium hydroxide.
By adding the mass of one mole of magnesium atoms, two moles of oxygen atoms, and two moles of hydrogen atoms, the molar mass is calculated to be 58.312g.

Step 2: Arrange the molar mass so the original units cancel and the desired units are on top

1.43 mol Mg (OH)2 X 58.312 Mg(OH)2
_____________= 83.3g Mg(OH)2
1 mol Mg(OH)2

The lines are suppose to be underneath the equation after the X, i don't know why it shows it on the side under the beginning of the equation
 
kevbo said:
LOL.

Education comes first.
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I understand what you are saying but somethings can be delivered in a different way, many people who sit in class struggle with Chemistry, and I can't promise I can help its been awhile since I sat in a chemistry class but I have a decent grasp on stoichiometry so why not show her the way to the road and she can travel it on her own?
 
Yeah I got that but in this problem you are calculating mole to mol and I can't remember if you need to change C2H6 to a mole by using the molar mass or not, and usually you use reactants with products and this is reactant with reactant...

I don't seem to be much help I have been out of school for awhile I'm sorry
 
ember said:
Yeah I got that but in this problem you are calculating mole to mol and I can't remember if you need to change C2H6 to a mole by using the molar mass or not, and usually you use reactants with products and this is reactant with reactant...

I don't seem to be much help I have been out of school for awhile I'm sorry
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haha its okay. When my chemistry teacher is giving out lectures for something like this, he doesn't always explain the little details. So, whenever that happens, its always on our own to try and figure this out.
 
I found another information from my packet from what my teacher has given me:

When the molar masses and molar relationship between reactants and products are known, chemist can calculate the amouts of material they need or will produce using a particular reaction.

might not be much of a help but thats what it said on the packet.
 
coolgirlspyer90 said:
I found another information from my packet from what my teacher has given me:

When the molar masses and molar relationship between reactants and products are known, chemist can calculate the amouts of material they need or will produce using a particular reaction.

might not be much of a help but thats what it said on the packet.
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yeah but thats when you are comparing products with reactants in your problem you are comparing reactants or at least that first one anyway
 
Man - I wish I could help, but I failed Chemistry in part due to not being able to understand the teacher. He was from Uganda, Africa and had a very heavy accent and I was severely hoh at the time with no hearing aids.
 
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