The tetraethyl lead Pb(C2H5)4 in a 25.00 mL sample of aviation gasoline was shaken with 15.00 mL of 0.02263 M I2. (Hint: one mole of I2 reacts with one mole of the tetraethyl lead). After the reaction was complete, the unused I2 was titrated with 8.74 mL of 0.03949 M thiosulfate solution. Calculate the weight of Pb(C2H5)4 (MW = 323.4 g/mol) in each liter of gasoline.

Caluclate the pH of a solution made by mixing 45.0mL of 0.25M HA (K _a= 2.5x10 ^-5) with 15.0mL of 0.75M NaOH

The time to rupture of an S-590 alloy exposed to a tensile stress of 140 MPa at 800C is 9.7 days. Compute the rupture lifetime of this alloy when subjected to a tensile stress of 140 MPa at 650C.

Please, explain in details. Thanks!

A piston-cylinder assembly contains 2.5 kg of saturated refrigerant R-134a with a quality of 10 % at 0 °C (State 1). There is a linear spring mounted on the piston such that when the mixture is heated the pressure reaches 1000 kPa with a volume of 70 L just as the piston touches the stop (State 2). The system is then heated further until a pressure of 1200 kPa is reached (State 3). a) Find the volume of the refrigerant in State 1. b) Calculate the work done by the device during the process from State 1 to State 3. c) Calculate the heat transfer required for this process. Also clearly indicate the direction of the heat transfer (whether into or out of the piston-cylinder system).

If the DCP solution is 0.01278M and you need 23.93 mLs of the DCP solution to completely react with the ascorbic acid, how many grams of ascorbic acid are in your sample? Do not write the answer in scientific notation. Make sure you use the correct number of significant figures and the correct units.

For a diatomic gas phase molecule, the rotational energy is given by the expression:

E_j = B_e J(J+1)

where J is the rotational quantum number, and B_e is the rotational constant. The degeneracy for rotational states is given by:

g(J) = 2J+1

The normalization constant (total rotational partition function) for the Boltmann distribution for rotations is given by:

Q(J,T) = k_BT / B_e

Iodine, I_{2(g), has a rotational constant of} B_e = 0.037372 cm^-1. Determine the fraction of I₂ molecules in the J= 25 state at T=300.0K.

(1 J/mol = 0.083595 cm^-1).

draw out the mechanism for synthesis Butyl acetate including a transition state

Suppose that in the synthesis of benzoic acid , a student uses 1.09 grams of magnesium , 7.83 grams of bromobenzene , and 21.196 grams of dry ice. If the mass of benzoic acid obtained were 4.13, what was the percent yield?

a) Calculate the pH of a 0.015M solution of formic acid, HCO2H?

Ka, HCO2H=1.8x10^-4    HCO2H(aq)-->HCO2^-(aq)+H^+(aq)

b) What is the concentration of HCO2H at equilibrium?

Compute the root-mean-square speed of Nemolecules in a sample of neongas at a temperature of 71°C.

Compare the osmotic pressure of water to pressure of red blood cells. Is water isotonic, hypertonic or hypotonic compared to red blood cells? Explain.

a. Briefly describe what a commutator is using words and an equation. How do commutators relate to the uncertainty principle?

b. Use the angular momentum commutators to show why we can not simultaneously determine the z-component of angular momentum and the x and/or y components.

A cylinder with a moveable piston contains 0.553 mol of gas and has a volume of 256 mL .

What will its volume be if an additional 0.246 mol of gas is added to the cylinder? (Assume constant temperature and pressure.)