Answer:
The molar concentration of hydrogen peroxide is 0.01164 M
Explanation:
<u>Step 1: </u>Data given
Volume of gas yielded = 75.3 mL = 0.0753 L
Temperature = 25.0 °C
Atmosphere = 0.976 atm
(Water = 0.032 atm at 25°C)
The original volume of H2O2 is 500 mL
Molar mass of O2 =32 g/mol
<u>Step 2:</u> The balanced equation
2H2O2(aq) → 2 H2O(l) + O2(g)
<u>Step 3:</u> Calculate pressure of O2
P = P(02) + P(water)
P(O2) = P - P(water)
P(O2) = 0.976 atm - 0.032 atm
P(O2) = 0.944 atm
<u>Step 4:</u> Calculate moles O2
p*V=n*R*T
⇒ with p = the pressure of O2 gas = 0.944 atm
⇒ with V= the volume of O2 = 0.0753 L
⇒ with n = the number of moles of O2
⇒ with R = the gas constant = 0.08206 L*atm/K*mol
⇒ with T = the temperature = 25°C = 298 Kelvin
n = (p*V)/(R*T)
n = (0.944 * 0.0753)/(0.08206*298K)
n = 0.00291 moles O2
<u>Step 5:</u> Calculate moles of H2O2
For 1 mole of O2 produced, we need 2 moles of H2O2
For 0.00291 moles O2 we need 2*0.00291 = 0.00582 moles H2O2
<u>Step 6:</u> Calculate molar concentration of H2O2
Molar concentration = moles / volume
Molar concentration = 0.00582 moles / 0.500L
Molar concentration = 0.01164 M
The molar concentration of hydrogen peroxide is 0.01164 M
