Chemistry Help Anyone? - TennisForum.com
 LinkBack Thread Tools
Old Dec 15th, 2006, 04:01 AM Thread Starter
Senior Member

Join Date: Nov 2004
Posts: 1,405

Chemistry Help Anyone?

PLEASE!!!
I know this is so basic, but I forget:

Which contains the same number of ions as the value of Avogadro's constant?
A) 0.5 mol NaCl
B) 0.5 mol MgCl2
C) 1.0 mol Na2O
D) 1.0 mol MgO

Apparently the answer is A, but I dunno why!
nbaker53 is offline
Sponsored Links
Advertisement

Old Dec 15th, 2006, 04:13 AM Thread Starter
Senior Member

Join Date: Nov 2004
Posts: 1,405

Re: Chemistry Help Anyone?

please!!!!
nbaker53 is offline
Old Dec 15th, 2006, 04:16 AM
Senior Member

Join Date: Nov 2004
Posts: 15,899

Re: Chemistry Help Anyone?

1 mol NaCl ---> `1 mol Na+ ions and 1 mol Cl- ions = 2 mol of ions = 2* Avogadro # of ions

0.5 mol NaCl = total of 1 mol of ions = Avogadro # of ions

0.5 mol of MgCl2 --> 1.5 *Avogadro # of ions
1 mol Na2O --> 3*Avogadro # of ions
1 mol MgO --> 2*Avogadro # of ions
LeRoy. is offline
Old Dec 15th, 2006, 04:20 AM Thread Starter
Senior Member

Join Date: Nov 2004
Posts: 1,405

Re: Chemistry Help Anyone?

Quote:
Originally Posted by Just_Me View Post
1 mol NaCl ---> `1 mol Na+ ions and 1 mol Cl- ions = 2 mol of ions = 2* Avogadro # of ions

0.5 mol NaCl = total of 1 mol of ions = Avogadro # of ions
So, you take the 2 x Avogradro's #
and then multiply by 0.5?

Also another question:

CO2 +3H2 --> CH3OH + H2O

What is the maximum amount of methanol that can be formed from 2 mol of carbon dioxide and 3 mol of hydrogen?

A) 1 mol
B) 2 mol
C) 3 mol
D) 5 mol
nbaker53 is offline
Old Dec 15th, 2006, 04:23 AM
Senior Member

Join Date: Nov 2004
Posts: 15,899

Re: Chemistry Help Anyone?

1 mol of CH3OH
LeRoy. is offline
Old Dec 15th, 2006, 04:24 AM Thread Starter
Senior Member

Join Date: Nov 2004
Posts: 1,405

Re: Chemistry Help Anyone?

Quote:
Originally Posted by Just_Me View Post
1 mol of CH3OH

And how'd you get that?
nbaker53 is offline
Old Dec 15th, 2006, 04:26 AM
Senior Member

Join Date: Nov 2004
Posts: 15,899

Re: Chemistry Help Anyone?

Quote:
Originally Posted by nbaker53 View Post
And how'd you get that?
from the eqn

1 mol of carbon dioxide with 3 mol of hydrogen gives 1 mol of methanol

2 mol of co2 would require 6 mol of h2 to give 2 mol of methanol

2 mol of co2 with 3 mol of h2 would give 1 mol of methanol and the extra mol of co2 will remain unreacted
LeRoy. is offline
Old Dec 15th, 2006, 04:28 AM Thread Starter
Senior Member

Join Date: Nov 2004
Posts: 1,405

Re: Chemistry Help Anyone?

Quote:
Originally Posted by Just_Me View Post
from the eqn

1 mol of carbon dioxide with 3 mol of hydrogen gives 1 mol of methanol

2 mol of co2 would require 6 mol of h2 to give 2 mol of methanol

2 mol of co2 with 3 mol of h2 would give 1 mol of methanol and the extra mol of co2 will remain unreacted
I don't understand how you got those values
What ratio are you using?
nbaker53 is offline
Old Dec 15th, 2006, 04:31 AM
Senior Member

Join Date: Nov 2004
Posts: 15,899

Re: Chemistry Help Anyone?

Quote:
Originally Posted by nbaker53 View Post
I don't understand how you got those values
What ratio are you using?
from the chemical eqn i got the values

multiply by 2 throughout to get the second set of numbers
LeRoy. is offline
Old Dec 15th, 2006, 04:33 AM Thread Starter
Senior Member

Join Date: Nov 2004
Posts: 1,405

Re: Chemistry Help Anyone?

Quote:
Originally Posted by Just_Me View Post
from the chemical eqn i got the values

multiply by 2 throughout to get the second set of numbers

I still don't understand?
Is there anyway you could make things more simpler?
nbaker53 is offline
Old Dec 15th, 2006, 04:37 AM
Senior Member

Join Date: Nov 2004
Posts: 15,899

Re: Chemistry Help Anyone?

CO2 +3H2 --> CH3OH + H2O

1 mol CO2 + 3 mol H2 ---> 1 mol CH3OH + 1 mol H2O

2 mol CO2 + 6 mol H2 ---> 2 mol CH3OH + 2 mol H2O
LeRoy. is offline
Old Dec 15th, 2006, 04:38 AM
Senior Member

Join Date: Sep 2003
Location: Nagoya, Japan
Posts: 20,868

Re: Chemistry Help Anyone?

CO2 +3H2 --> CH3OH + H2O

you got that... you see that you need 1 mol CO2 and 3 mol H2 to get one mol Ch3OH, right? so if you you have 2 mol CO2 it would look like this :

2CO2 + 6H2 --> 2CH3OH + 2H2O

but you do not have 6 mol H2, you only have three which means it doesnt matter if you have 1 mol or two 2 CO2; as long as you only have 3 mol H2 you can only get 1 mol CH3OH out of it

my tennis pictures: here and here
my tennis videos: here
rrfnpump is offline
Old Dec 15th, 2006, 04:40 AM Thread Starter
Senior Member

Join Date: Nov 2004
Posts: 1,405

Re: Chemistry Help Anyone?

Quote:
Originally Posted by rrfnpump View Post
CO2 +3H2 --> CH3OH + H2O

you got that... you see that you need 1 mol CO2 and 3 mol H2 to get one mol Ch3OH, right? so if you you have 2 mol CO2 it would look like this :

2CO2 + 6H2 --> 2CH3OH + 2H2O

but you do not have 6 mol H2, you only have three which means it doesnt matter if you have 1 mol or two 2 CO2; as long as you only have 3 mol H2 you can only get 1 mol CH3OH out of it
Okay, I think I sort of get it! Thanks
nbaker53 is offline
Old Dec 15th, 2006, 04:40 AM
Rest In Peace, Elena

Join Date: Sep 2005
Location: Melbourne
Posts: 19,638

Re: Chemistry Help Anyone?

i thought this thread was about how to find a chemtry between a guy and girl - Just make eye contact with other!

Rest In Peace, Elena Baltacha
Brett. is offline
Old Dec 15th, 2006, 04:46 AM Thread Starter
Senior Member

Join Date: Nov 2004
Posts: 1,405

Re: Chemistry Help Anyone?

Okay, another question. Not related to moles and stuff like that:

What statement is a correct description of electron loss in this reaction?

2Al + 3S --> Al2S3

A) Each aluminium atom loses two electrons
B) Each aluminium atom loses three electrons
C) Each sulfure atom loses two electrons.
D) Each sulfure atom loses three electrons.

I know this is so basic, I just can't remember any of this!
nbaker53 is offline

Quick Reply
Message:
Options

## Register Now

In order to be able to post messages on the TennisForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
 Please enter a password for your user account. Note that passwords are case-sensitive. Password: Confirm Password:
Email Address
 Please enter a valid email address for yourself. Email Address:
OR

## Log-in

 User Name Password Remember Me?
Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

 Thread Tools Show Printable Version Show Printable Version Email this Page Email this Page

 Posting Rules You may not post new threads You may post replies You may not post attachments You may not edit your posts BB code is On Smilies are On [IMG] code is On HTML code is OffTrackbacks are On Pingbacks are On Refbacks are On Forum Rules

For the best viewing experience please update your browser to Google Chrome
 Terms of Use