• We’re currently investigating an issue related to the forum theme and styling that is impacting page layout and visual formatting. The problem has been identified, and we are actively working on a resolution. There is no impact to user data or functionality, this is strictly a front-end display issue. We’ll post an update once the fix has been deployed. Thanks for your patience while we get this sorted.

Electrolysis Question (high school level)

A

acidvoodoo

Platinum Member
got a question, that i'm not completly sure about, (it's on a really old practice paper, so my newer books don't cover it)

the question was about the electrolysis

anyway, question was

Balence the half equation---- .......H+ + .........e- ----->H2 (little 2)

i got 2H+ + 2e- ------>H2 (little 2)

i figured having 2 H's was required for the other side to balence, then the 2e's were required for the charges to balence


what is this reaction called, decomposition, neutralisation, oxidation, or reduction. i figured as no electrons were gained or lost that it must be neutralisation


thanks for help
 
Originally posted by: acidvoodoo


i figured having 2 H's was required for the other side to balence, then the 2e's were required for the charges to balence

what is this reaction called, decomposition, neutralisation, oxidation, or reduction. i figured as no electrons were gained or lost that it must be neutralisation
Click to expand...

If you just added 2 electrons, how is that not electrons gained?

Here is how you remember oxidation/reduction

Reduction actually reduces the charge of the molecule : this means electrons were added
Oxidation means the charge goes up : meaning electrons lost

Therefore, this is reduction.

-silver

 
another one i'm stuck on is


in an experiement the student collected 24cm3(cubed) of chlorine gas, Cl2 (little 2), at room temperature and pressure. Calculate the mass of this volume of gas. RAM of Cl=35.5 (the volume of any gas at room temperature and pressure is 24 litres)

i definetly have not covered volumes, so i am unsure how to wok this one out 🙁
 
Originally posted by: agnitrate
Originally posted by: acidvoodoo


i figured having 2 H's was required for the other side to balence, then the 2e's were required for the charges to balence

what is this reaction called, decomposition, neutralisation, oxidation, or reduction. i figured as no electrons were gained or lost that it must be neutralisation
Click to expand...

If you just added 2 electrons, how is that not electrons gained?

Here is how you remember oxidation/reduction

Reduction actually reduces the charge of the molecule : this means electrons were added
Oxidation means the charge goes up : meaning electrons lost

Therefore, this is reduction.

-silver
Click to expand...

Be careful with that definition... Reduction means the charge becomes more negative seems a little better. You can increase the charge on something by adding electrons to it. It will be highly charged. I know it's sort of splitting hairs, but I'm trying to help avoid confusion.
 
Originally posted by: agnitrate
Originally posted by: acidvoodoo


i figured having 2 H's was required for the other side to balence, then the 2e's were required for the charges to balence

what is this reaction called, decomposition, neutralisation, oxidation, or reduction. i figured as no electrons were gained or lost that it must be neutralisation
Click to expand...

If you just added 2 electrons, how is that not electrons gained?

Here is how you remember oxidation/reduction

Reduction actually reduces the charge of the molecule : this means electrons were added
Oxidation means the charge goes up : meaning electrons lost

Therefore, this is reduction.

-silver
Click to expand...


i think i though that none were gained, because the charges balenced, silly me
 
Originally posted by: acidvoodoo
another one i'm stuck on is


in an experiement the student collected 24cm3(cubed) of chlorine gas, Cl2 (little 2), at room temperature and pressure. Calculate the mass of this volume of gas. RAM of Cl=35.5 (the volume of any gas at room temperature and pressure is 24 litres)

i definetly have not covered volumes, so i am unsure how to wok this one out 🙁
Click to expand...


use perfect gas law: pV = nRT
solve for moles of gas (n), then convert to mass
 
Originally posted by: silverpig


Be careful with that definition... Reduction means the charge becomes more negative seems a little better. You can increase the charge on something by adding electrons to it. It will be highly charged. I know it's sort of splitting hairs, but I'm trying to help avoid confusion.
Click to expand...

Very true. I was just trying to get him to associate reduction with reduced charge because they sound the same but go w/ silverpig's definition, acidvoodoo.

-silver

 
Originally posted by: bolomite
Originally posted by: acidvoodoo
another one i'm stuck on is


in an experiement the student collected 24cm3(cubed) of chlorine gas, Cl2 (little 2), at room temperature and pressure. Calculate the mass of this volume of gas. RAM of Cl=35.5 (the volume of any gas at room temperature and pressure is 24 litres)

i definetly have not covered volumes, so i am unsure how to wok this one out 🙁
Click to expand...


use perfect gas law: pV = nRT
solve for moles of gas (n), then convert to mass
Click to expand...

well,i definetly have never seen that before, can you give a brief explanation how to use it? like what numbers go where
 
haven't seen it?! :Q 😀

p = pressure
V = volume
n = # of moles
R = universal gas constant, 0.08206 L atm / mol K
T = temperature

just solve for n, make sure all your units are consistent
 
Originally posted by: acidvoodoo
Originally posted by: bolomite
Originally posted by: acidvoodoo
another one i'm stuck on is


in an experiement the student collected 24cm3(cubed) of chlorine gas, Cl2 (little 2), at room temperature and pressure. Calculate the mass of this volume of gas. RAM of Cl=35.5 (the volume of any gas at room temperature and pressure is 24 litres)

i definetly have not covered volumes, so i am unsure how to wok this one out 🙁
Click to expand...


use perfect gas law: pV = nRT
solve for moles of gas (n), then convert to mass
Click to expand...

well,i definetly have never seen that before, can you give a brief explanation how to use it? like what numbers go where
Click to expand...

P = pressure (kPa)
V = volume (L)
n = number of moles
R = gas constant (8.31 I think?)
T = temperature (K)

Room temperature and pressure is ~ 101.3 kPa and 293 K I think. Look it up to be sure though.
 
n=0.08206 liters * atm / (mol * liters)

Oh one more cool gimmick:
OILRIG:

Oxidation is losing (electrons)
Reduction is gaining (electrons).

Of course, having oxidizing agents and reducing agents makes stuff sooo confusing! AP Chem 😛 Glad it's over with...
 
You must log in or register to reply here.

TRENDING THREADS

Back
Top