Calculate the quantity of electricity, in coulombs, needed to produce 18 cm3 of chlorine gas. *( 1 Faraday= 96500 coulombs)
Okay. LET'S DO IT. I'll do every single step (: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1) First we must find the number of moles in the 18 cm3 of chlorine gas. V=nmv ( volume= moles x molar volume) 18cm3 = moles x 24000cm3 <--- same units!! rearrange it to get moles.
18cm3/ 24000cm3 = moles = 0.00075
2) Write down the half equation.
2Cl' > Cl2 + 2e'
3) Electricity always refers to "flow of electrons"
2e' ( 2 electrons) are need to produce chlorine gas.
2 electrons= 96500 x 2 2 e'= 193000 C
4) BUT what about the moles? just you wait...
now times the number of coulombs by the amount of moles calculated in part 1)
193000 x 0.00075= 144.75 Coulombs are need to produce 18 cm3 of chlorine gas.
AND all done!! hope you understood and this helped (:
I just noticed, it's 96500, not 95600
ReplyDeleteOops :/ Thanks for pointing it out!
DeleteI thought it was 96,000??
ReplyDeletewhatever it is,its value will be given in the question.
ReplyDeleteThis comment has been removed by the author.
ReplyDeleteE.G (question 5 from paper 2C May 2012. KCHO/2C)
ReplyDeleteCalculate the quantity of electricity, in coulombs, needed to produce 18 cm3 of chlorine gas. *( 1 Faraday= 96500 coulombs)
Okay. LET'S DO IT. I'll do every single step (:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1) First we must find the number of moles in the 18 cm3 of chlorine gas.
V=nmv ( volume= moles x molar volume)
18cm3 = moles x 24000cm3 <--- same units!!
rearrange it to get moles.
18cm3/ 24000cm3 = moles = 0.00075
2) Write down the half equation.
2Cl' > Cl2 + 2e'
3) Electricity always refers to "flow of electrons"
2e' ( 2 electrons) are need to produce chlorine gas.
2 electrons= 96500 x 2
2 e'= 193000 C
4) BUT what about the moles? just you wait...
now times the number of coulombs by the amount of moles calculated in part 1)
193000 x 0.00075= 144.75 Coulombs are need to produce 18 cm3 of chlorine gas.
AND all done!! hope you understood and this helped (:
thank you
Delete