The initial rate of reaction for H2O2(aq) <-> H2O (l) 1/2 O2 (g)
is found to be 1.7x10(-3)M/s. Assume that this rate holds for 2 minutes. Start with 160ml of 1.60 M H2O2.
How many milliliters of O2 measured at 24C and 760mmHg , are released from solution in the first minute of the reaction?
I tried to calculate the new concentration of H2O2, assuming it was a zero order reaction from the units of the k. I used the eqn:
ln(conc(At))=-kt+ln(conc(Ao)).
I got k from using RxnRate=k*(conc(Ao)
Then i was thinking about finding the Ksp value and doing an ice table. Solving for the conc of O2, then using PV=nRT and the molarity to find the V. Is this method right or? :s
To find the number of milliliters of O2 released from the solution in the first minute of the reaction, you can follow these steps:
Step 1: Calculate the initial moles of H2O2:
Molarity (M) = moles/volume (L)
Given: Volume = 160 mL = 0.160 L
Molarity of H2O2 (Ao) = 1.60 M
moles of H2O2 (Ao) = Molarity (Ao) x Volume (L)
moles of H2O2 (Ao) = 1.60 M x 0.160 L
Step 2: Calculate the concentration of H2O2 after 1 minute:
We assume a zero-order reaction, which means the concentration of H2O2 changes linearly with time:
conc(At) = (-k x t) + conc(Ao)
Given:
Initial rate of the reaction, k = 1.7 x 10^(-3) M/s
Time, t = 1 minute = 1/60 hour
To find K (rate constant), rearrange the rate equation:
Rate = k x [H2O2]^0 =[H2O2]^0
k = Rate / [H2O2]^0
k = 1.7 x 10^(-3) M/s / (1.60 M)
Now, substitute the values in the equation to find the concentration of H2O2 after 1 minute:
conc(At) = (-k x t) + conc(Ao)
conc(At) = (-1.7 x 10^(-3) M/s) x (1/60 hour) + (1.60 M)
Step 3: Calculate the moles of O2 released:
Given: The balanced equation is H2O2(aq) <-> H2O(l) + 1/2 O2(g)
From the balanced equation, we can see that for every 1 mole of H2O2 that reacts, 1/2 mole of O2 is produced.
Therefore, the moles of O2 released is equal to the moles of H2O2 reacted.
moles of O2 released = moles of H2O2 reacted = conc(Ao) - conc(At)
Step 4: Calculate the volume of O2 released:
Use the ideal gas equation, PV = nRT, where:
P = pressure (760 mmHg)
V = volume (unknown)
n = moles of O2 released
R = ideal gas constant (0.0821 L·atm/mol·K)
T = temperature (24°C = 24 + 273 = 297 K)
Rearrange the equation to solve for V:
V = (nRT) / P
Substitute the values and solve for V.
This method should give you the volume of O2 released from the solution in the first minute of the reaction.