Cyclopropane, c3h6, is converted to its isomer propylene, ch2=chch3, when heated. the rate law is first order in cyclopropane, and the rate constant is 6.0 × 10−4/s at 500°c. if the initial concentration of cy- clopropane is 0.0226 mol/l, what is the concentration after 525 s?

0.011 M

Explanation:

Expression for rate law for first order kinetics is given by:

where,

k = rate constant  =

t = time taken   = 525 sec

a = initial amount of the reactant  = 0.0226 mol/L

a - x = amount left = ?

Now put all the given values in above equation, we get

Thus the concentration after 525 s is 0.011 mol/L.

2fe + 3h2so4 -> fe2(so4)3 + 3h2

it is necessary to balance equations in order to get the proper amount of reactants as well as products in order not to make a miscalculation.

you cannot change the subscripts as that would change the substance itself. for instance, diatomic elements such as h2 only have the subscript two when a gas. another example would be so4, if you were to change the subscript, the element would no longer be sulfate.

we change the coefficients instead as that only changes the number of molecules rather than the substance itself.

hope this !