Chemistry problem help

Anything else. Post a funny site or tell us about yourself. Discuss current events or whatever else you want. Post off topic threads here.
Post Reply
User avatar
nitrofreez
Regular Member
Posts: 312
Joined: Thu Dec 27, 2007 9:40 pm
Quick Reply: Yes
Location: Off Topic
Contact:

Chemistry problem help

Post by nitrofreez »

So I've gotten some homework for chemistry, and the last question is:

How many molecules (not moles) of NH3 are produced from 6.42×10^−4 g of H2?

Chemical formula: 3H2 (g) + N2 (g)---> 2NH3 (g)

I've been trying this problem for a while but I still can't get it. So,my question is, how would I go about solving this problem? Any help is much appreciated.

-Nitro


EDIT: It's 6.42×10^−4 not 10-4, sorry. Thanks crazy.
Last edited by nitrofreez on Sat Sep 20, 2008 7:53 pm, edited 1 time in total.
BF3 ID: Alpinewolf007
Though I Fly Through the Valley of Death, I Shall Fear No Evil. For I am at 80,000 Feet and Climbing.
Image

User avatar
ThiefzV2
Active Member
Posts: 566
Joined: Thu Jan 25, 2007 10:02 pm
Quick Reply: Yes
Location: Off Topic

Re: Chemistry problem help

Post by ThiefzV2 »

5.56x10^20
Last edited by ThiefzV2 on Sat Sep 20, 2008 7:45 pm, edited 1 time in total.
Image :)
Image

User avatar
crazyskwrls
Advanced Member
Posts: 2293
Joined: Sun Aug 19, 2007 10:16 pm
Quick Reply: Yes
Location: Off Topic

Re: Chemistry problem help

Post by crazyskwrls »

ThiefzV2 wrote:5.56x10^20

i beg to differ, 1.28*10^20


6.42×10−4 g
i guess this is supposed to be 6.42×10^−4 g
Image Image
thnx Kraq

User avatar
ThiefzV2
Active Member
Posts: 566
Joined: Thu Jan 25, 2007 10:02 pm
Quick Reply: Yes
Location: Off Topic

Re: Chemistry problem help

Post by ThiefzV2 »

6.42×10−4 g
i guess this is supposed to be 6.42×10^−4 g


yes thats what he meant


crazyskwrls wrote:
ThiefzV2 wrote:5.56x10^20

i beg to differ, 1.28*10^20


No
Image :)
Image

User avatar
nitrofreez
Regular Member
Posts: 312
Joined: Thu Dec 27, 2007 9:40 pm
Quick Reply: Yes
Location: Off Topic
Contact:

Re: Chemistry problem help

Post by nitrofreez »

Incidentally, would you be able to explain to me how you got the answer Crazy? You were right but I'd like to know how you did it for future reference
BF3 ID: Alpinewolf007
Though I Fly Through the Valley of Death, I Shall Fear No Evil. For I am at 80,000 Feet and Climbing.
Image

User avatar
crazyskwrls
Advanced Member
Posts: 2293
Joined: Sun Aug 19, 2007 10:16 pm
Quick Reply: Yes
Location: Off Topic

Re: Chemistry problem help

Post by crazyskwrls »

ThiefzV2 wrote:
6.42×10−4 g
i guess this is supposed to be 6.42×10^−4 g


yes thats what he meant


crazyskwrls wrote:
ThiefzV2 wrote:5.56x10^20

i beg to differ, 1.28*10^20


No


pwned :D

6.42×10^−4 g
H2 has molar mass of 2
6.42×10^−4 g/2 = 3.21×10^−4 mol of H2

since according to the equation for every 3 mol of H2, 2 mol of NH3 is produced so

3.21×10^−4 mol of H2 * (2/3) = 2.14*10^-4 mol of NH3

avogadro's number is 6.02*10^23

2.14*10^-4 mol of NH3 * 6.02*10^23 = 1.28*10^20

:)
Image Image
thnx Kraq

User avatar
nitrofreez
Regular Member
Posts: 312
Joined: Thu Dec 27, 2007 9:40 pm
Quick Reply: Yes
Location: Off Topic
Contact:

Re: Chemistry problem help

Post by nitrofreez »

I put in his answer and it came up as correct mate. I tried your answer too but it was wrong.

Thanks, a lot mate. Really appreciate it
Attachments
chem2.jpg
chem2.jpg (21.13 KiB) Viewed 1152 times
Last edited by nitrofreez on Sat Sep 20, 2008 8:18 pm, edited 1 time in total.
BF3 ID: Alpinewolf007
Though I Fly Through the Valley of Death, I Shall Fear No Evil. For I am at 80,000 Feet and Climbing.
Image

User avatar
SM-Count
Ex-Staff
Posts: 2761
Joined: Sat Jan 12, 2008 7:02 pm
Quick Reply: Yes
Location: /wave

Re: Chemistry problem help

Post by SM-Count »

Crazy has the correct answer but the wrong explanation. You never use H2 to calculate molar mass, you use H with 1g, but the conversion ration 6 moles of hydrogen to 2 moles of ammonia.
Last edited by SM-Count on Sat Sep 20, 2008 8:18 pm, edited 1 time in total.

User avatar
ThiefzV2
Active Member
Posts: 566
Joined: Thu Jan 25, 2007 10:02 pm
Quick Reply: Yes
Location: Off Topic

Re: Chemistry problem help

Post by ThiefzV2 »

well it was worth a try :P


crazy, do my HW too plz
Image :)
Image

User avatar
Ashikiheyun
Loyal Member
Posts: 1821
Joined: Mon Feb 19, 2007 8:08 am
Quick Reply: Yes
Location: CMA

Re: Chemistry problem help

Post by Ashikiheyun »

Lord how I do NOT miss chemistry at all.
:banghead:
Playing on Devias SRO - Ashikiheyun if you want a guild PM me here or in-game.

Post Reply

Return to “Off Topic Lounge”