1) How many milliliters of 0.480M NaOH would be required to titrate a 5.00ml solution of 0.320M H2SO4? Report answer to the correct number of significant figures.
2) Write a balanced equation for the combustion of octane, C8H18.
3) If the standard enthalpy of formation (deltaHf) of methanol, CH3OH, is -238.6kJ/mol, deltaHf(CO2(g))=-394kj/mol, and deltaHf(H20(l))= -286kJ/mol, calculate the standard heat of combustion of methanol. Report the answer to the correct number of significant figures.
4) If a gas sample absorbs 89kJ of heat and does 120 kJ of work, what is the change in its internal energy? Report your answers to the correct number of significant figures.
5) What is the wavelength of a photon of electromagnetic radiation having a photon energy of 4.56X10^-19 J? Report your answer in nanometers, to the correct number of significant figures.
This solution provides answers to various questions regarding titration, balanced equations, standard enthalpy of formation, change in internal energy, and wavelength of a photon.
Five physical chemistry questions.
5) Ozone decomposes to oxygen according to the balance chemical equation below:
2O3 ---> 3O2
If the rate of disappearance of the ozone is -7.2E-4 M/s, what is the rate of formation of oxygen?
6) If 100kJ of heat is added to 54.0 g of water at 100°C, what is the final state of the water?
MW H2O = 17.9 g/mole
7) How many grams of NaCl do you need to add to 5.00 kg of water to make a solution that freezes at -
10.0°C (assume an ideal solution)? MW NaCl = 58.4 g/mole
8) If an individual records a blood alcohol level of 0.0267M (0.16% by volume), what will this person's
blood alcohol level be 4 hours later if the rate constant for the oxidation of ethanol in the liver is 0.00425
10) The reaction of NO and O2 produces NO2
2NO(g) + O2(g) ---> 2 NO2(g)
The rate constant is second order with respect to NO(g) and first order with respect to O2(g). At a given temperature, the rate constant, k, equals 6.1E3 M-2S-1. What is the rate of reaction when the initial concentrations of NO and O2 are 0.020 M and 0.015 M respectively?
Potentially useful information
PV = nRT
ln(A/Ao) = -kt
1 atm = 760 mmHg
lnP = (- H/RT) + c
1/A - 1/Ao = kt
Room temperature = 25°C = 298K
ln (P2/P1) = (H/R)(1/T1-1/T2)
Ao - A = kt
R = 8.31 J/(mol K) = 0.0821 (L atm)/(mol K)
T = Kmi
t1/2 = 0.693/k
Kbp for water: 0.512°C/m
Pa = Xa Pa
kH for N2 = 8.42E-7 M/ mmHg
Kfp for water: -1.86°C/m