Molecular iodine, i2 (g), dissociates into iodine atoms at 545k with a first order rate constant of 0.344 1/s. if you start with 0.054 m i2 at this temperature how much will remain after 5.16 s?

0.00915 M of remain after 5.16 seconds.

Explanation:

Using integrated rate law for first order kinetics as:

Where,  

is the concentration at time t

is the initial concentration

Given that:

The rate constant, k = s⁻¹

Initial concentration = 0.054 M

Final concentration = ? M

Time = 5.16 s

Applying in the above equation, we get that:-

0.00915 M of remain after 5.16 seconds.

i just got this problem. it's 90.3

first, consult an activity series chart to determine if al is more reactive than fe. it is, so it will replace the fe. now, one can continue with the problem.

next, make sure you have a correctly balanced equation.

3feo + 2al ==> 3fe + al2o3

now, determine which reactant (feo or al) is in limiting supply.

moles feo present = 125 g x 1 mole/71.8 g = 1.74 moles

moles al present = 25.0 g x 1 mole/26.98 g = 0.927 moles

since from the balanced equation, it take 3 mol feo for every 2 mol al, al will be limiting.

you can determine this simply by dividing moles of each by their coefficient in the balanced equation. for example: 1.74/3 = 0.58 and 0.927/2 = 0.464. al is less, so it is limiting.

finally, using the stoichiometry in the balanced eq. determine mass of fe that can be produced from 0.927 moles of al.

0.927 moles al x 3 moles fe/2 moles al x 55.8 g/mole = 77.6 g