help! (Basic level-stoichiometry).
You are currently reading a thread in /wsr/ - Worksafe Requests
We respect your right to privacy. You can choose not to allow some types of cookies. Your cookie preferences will apply across our website.
Can /wsr/ help me with this?
>>112744
>based on the reaction above
presumably meaning the numerical values given in the example
consider H2SO4 to be a strong acid, ie fully dissociated, then final [H+] = the initial [H2SO4] so 0.13 M
(IIRC pKa of H2SO4 and H3O+ (hydronium) are similar so the above might not really be true but good enough for the problem so far).
>[KI]
literally plug n chug this is a dilution
0.025M*(1/10) = 0.0025M
>[iodide]
The two species K+ and I- are in a 1:1 ratio, so the concentration of K+ is the same of that of I-.
>[H2O2]
another plug n chug
>[S2O3]2-
>again just multiply the values given
Thank you. I understand this is kiddie level stuff, but I have left it to the last minute.
>>112746
for the dilutions the formula being used is
m_1*V_1 = m_2*V_2
m_2 = (m_1)(V_2/V_1)
>>112748
also, equilibrium calculations (slightly more complicated than the problems you posted) are generally performed using an "ICE" or "RICE" table.
https://en.wikipedia.org/wiki/RICE_chart
>>112751
I have no idea.
Once I finished electron geometry and molecular orbital theory without any trouble, but I've gotten completely lost on this area.
Honestly I can't understand what I'm supposed to do on the calculator for the next few quesitons.
I never chose to take final 2-years of highschool Chemistry or even Mathematics, I always interested in Languages and history.
But my parents pressured me into taking chemistry at university. At this point I don't feel like I can keep up anymore. The frustrating thing is I know it's basic level stuff, but I don't have any backround in what a reagent is and I'm totally miserable doing this subject.
I can't just quit though if I ever want to study anything else at Uni again. Right?
>>112755
>I can't understand what I'm supposed to do on the calculator for the next few quesitons
Look at the units, always. (This is called dimensional analysis).
The dilution calculations return a value in concentration (M) b/c (cm^3/cm^3) cancel out.
This is the text I recommended.
http://libgen.io/search.php?req=zumdahl+chemical+principles&lg_topic=libgen&open=0&view=simple&res=25&phrase=1&column=def
>I can't just quit though if I ever want to study anything else at Uni again.
no, I guess you can't quit
>>112749
>m_2 = (m_1)(V_2/V_1)
m_2 = (m_1)(V_1/V_2)
fug