PDA

View Full Version : help me with ap chem xD


zeratul90
12-06-2009, 08:09 PM
Ok, does anyone know how to calculate the energy absorbed to produce water vapor? I was given the molar head of vaporization for water which is 40.79 kj/mol, but i'm not sure wtf i'm supposed to do with it.

Also, i need to calculate the total heat gained by water in the calorimeter which would be the heat gained of H2O(liquid) + heat gained of H20(gas). Calculating them would simply be using the q=mc*delta t but, how do i calculate the temperature of the water vapor?

Thanks! :)

Court_Jester
12-06-2009, 09:16 PM
The problem is incomplete. Can you provide the complete statement of the problem? Are you supposed to vaporize all of the water?

Bud
12-06-2009, 10:33 PM
Ok, does anyone know how to calculate the energy absorbed to produce water vapor? I was given the molar head of vaporization for water which is 40.79 kj/mol, but i'm not sure wtf i'm supposed to do with it.

Also, i need to calculate the total heat gained by water in the calorimeter which would be the heat gained of H2O(liquid) + heat gained of H20(gas). Calculating them would simply be using the q=mc*delta t but, how do i calculate the temperature of the water vapor?

Thanks! :)

Something's missing... transcribe the entire problem.

Do you mean the energy required to vaporize a certain volume of water?

edberg505
12-07-2009, 03:49 AM
Yeah, I'm with everyone else here. I think something is lost in translation. Need to see the entire problem in full.

zeratul90
12-07-2009, 08:05 PM
nvm guys, i asked my friends today at school how it was supposed to be done (rather i just copied), apparently they were too "busy" last night to respond to me when i sent a message every hour from 5pm-12pm -_- Thanks though!