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need serious chem help !!

:confused: Ok im doing an investigation to see the effect of varying the concentration on the reaction between HCl and Mg .. the weight of Mg was kept constant .. it was 0.055g ...
ok what would the rate equation be ?
I also have to find the rate constant but dont know how too ...
for example if the rate is 0.60 at 1M (conc of HCl) then what would the rate constant be??
.. please please i hav to give the thing by fri and i need help !!!
ammarb87
:confused: Ok im doing an investigation to see the effect of varying the concentration on the reaction between HCl and Mg .. the weight of Mg was kept constant .. it was 0.055g ...
ok what would the rate equation be ?
I also have to find the rate constant but dont know how too ...
for example if the rate is 0.60 at 1M (conc of HCl) then what would the rate constant be??
.. please please i hav to give the thing by fri and i need help !!!



Whenever you have a solid it is not implicated in the rate equation...

therefore Mg is not involved and the rate equation becomes

Rate = k[H+]^x

Perform various experiments changing the concentration of the acid and plot the rate against the concentration of the acid (either measure average rate over the first part of the reaction or initial rate)

Horizontal straight line graph ... x=0
Proportional straight line and x=1
Curve and x = something else !

If x = something else then plot log rate against log concentration and x= gradient intercept = logk
Reply 2
ok another qustion .. what would the untis for rate constant be if i measured the rate in (cm3s-1) and conc in mol dm-3 .. help plllease !!!
Reply 3
Depends on the order of the reaction as the units have to make the rate equation consistent.

So for example:

if it is first order

rate = k [A]

k = rate / [A]

units of k are cm^3 s^-1 (mol/dm3)^-1

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