Question

hey u guys
Plz help

Answer 1

Okay, let's write out the balanced equation first.

\[1. H_{2(g)}+ I_{2(g)} \rightarrow 2HI_{g}\]

Answer 2

yes i got that

Answer 3

how do we find the limiting reagent?

Answer 4

Good question: it doesn't say how many moles/grams of each starting material we have

Answer 5

do you have this information?

Answer 6

wait there is a drawing on the bottom of the page, leeme attach it
gimme a min

Answer 7

thats all the info i have

Answer 8

so we've got 7 molecules of H2 and 4 molecules of I2

Answer 9

yes

Answer 10

so finding the limiting reagent is easy:

since this is a 1:1 molar ratio we would need to have an equal amount

7 molecules of hydrogen
7 molecules of I2

but we have

7 molecules of hydrogen gas
4 molecules of I2

so we know right away that I2 is limiting because that's going to run out first.

Answer 11

how is it one to one ratio?

Answer 12

sorry im trying to make sure i understand this

Answer 13

one mole of hydrogen gas reacts with one mole of iodine to for 2 moles of HI

Answer 14

that's from our balanced chemical reaction

Answer 15

yes i get that but dont u look on the other side of the equation for your ratio as well?

Answer 16

no, the reason is that we want to figure out how much of each reactant we need. whatever reactant runs out first that's called the limiting reagent we then use that to figure out how much product we have

Answer 17

oh ok i understand

Answer 18

so what do we do next

Answer 19

we need seven molecules of iodine and seven molecules of hydrogen for the reaction to go to completion.

but we only have four molecules of I2

so to figure out how much product we would get

we would do this we would multiply the limiting reagent in this case iodine by the molar ratio to get our product.

\[4~molecules~I_{2}*(\frac{ 2HI }{ I_{2} }) = 8~molecules~of~HI\]

Answer 20

for C @popcornfun we know that we have 3 molecules of HI remaining

Answer 21

and we must add 3 more molecules of I2 for the reaction to go to completion

Answer 22

@popcornfun

Answer 23

ok so for D do we use the info from C?

Answer 24

@Photon336

Answer 25

yes so you know you have 3 molecules of H2 left over

Answer 26

so you would need 3 more molecules of I2 to make the reaction go to completion.

Answer 27

ohhhh ok

Answer 28

Thank you so much :) @Photon336

Answer 29

No problem man anytime

Answer 30

i might bother u again in the future dude
im apologizing in advance XD
@Photon336

Answer 31

yeah don't worry ask away