How do you know when it is acceptable to assume a heat capacity is constant and pull it outside of the integral?

In a reaction of Zn (0.53 g) & HCl what is the volume of Hydrogen gas generated? (assume atmospheric pressure)

Consider the equilibrium reaction shown below, which is first order with respect to each [A], [B], [C], and [D].

A + B = C + D with K1 for the forward reaction and K2 for the reverse reaction.

Use the following data:

For T=300K we have Keq= 9*10^-3 and K1=21.3 M^-1 sec^-1

For T=350K we have Keq= 1.6*10^-2 and K1= 3,696 M^-1 sec^-1

A) Find the activation energies for the forward and backward reaction (Eaf and Eab) and the pre-expontential factors (Af and Ab) in the Arrhenius rate expressions for k1 and k2.

B) A catalyst is added to the solution. It is found that the forward rate of the catalyzed reaction at 300 K, k1cat(300K), is equal to that for the uncatalyzed reaction (k1) at 600 K.

i) What is the equilibrium constant Keq(cat) of the catalyzed reaction at 300 K?

ii) What are the forward and backward activation energies (Ea(fc) and Ea(bc)) in the presence of the catalyst?

A single charcoal briquette has a mass of 0.1 kg, and is made up of almost entirely carbon. I want to burn that briquette in air in a sealed oven. When the combustion is complete, the gases in the oven will include CO2,O2,and N2, and the mole fraction of CO2 in this exhaust is 5%. How much air is needed (before the combustion)? Give your answer as kg, kg mole, and as a volume in m^3. For the last part, you'll use the ideal gas law. Assume that p= 1 atm, and T=400C

3,4-benzopyene (BP, C20H12) is a toxic aromatic hydrocarbon frequently found in polluted air. 5.0 liters of air (at standard temperature and pressure) is bubbled through 10 ml of dilute sulfuric acid, capturing the BP. 3.0 ml of this solution is diluted to 10 ml, and this final solution gives a fluorescence intensity of 205 (arbitrary units). A blank gave an intensity of 35 (same units). A solution containing 0.75 mg of BP per ml is prepared and 1.5 ml of the this solution is added to 3.0 ml of the initial BP solution, prior to dilution to 10 ml. This solution gives a fluorescence intensity of 294 (arbitrary units).

a) Calculate the mass of BP per liter of air.

b) Express this answer in terms of ppm and ppmv.

The enthalpy of a simple (and not particularly realistic) model system is given by

H = c1 TP + c2T² /2

where c1 and c2 are constants.

1. Evaluate the partial derivatives (∂H/∂T)_p and (∂H / ∂P)_t . Demonstrate that these partial derivatives satisfy the appropriate Maxwell relations and also determine cP.

2. Construct the inexact differentials (dH)_T, (dH)_P, and the exact differential, dH .

3. Integrate these three differential quantities along the following two paths that connect the same two equilibrium states: (T1, P1) to (T2, P2).

Path 1: The temperature is first increased to T2 at constant pressure, P1. The pressure is then increased to P2 at constant temperature, T2.

Path 2: The pressure is first increased to P2 at constant temperature, T1. The temperature is then increased to T2 at constant pressure, P2.

Compare the integrated values for (ΔH)_T, (ΔH)_P, and ΔH obtained along the two paths.

A mixture containing an initial concentration of 0.1726 M for H2 and 0.1361 M for I2 is allowed to come to equilibrium (see reaction below). What must be the equilibrium concentration of HI? H2(g) + I2(g) ↔ 2HI(g) Kc = 48.7000

At a temp below room temp but with all components as gases, the decomposition of iodine monochloride, ICl, to iodine and chlorine, is 1.4*10^-5

2ICl (g)----> I2 (g) + Cl2 (g)

If a sealed vessel has [ICl]=1.87 M, and no iodine or chlorine. What are the equilibrium cocentrations?

Calculate the pH of a liter of 0.125 M ammonium perchlorate solution. (kb= 1.7 x 10^-5)

show ice chart!

A window of a car is found to be covered with 0.9cm of ice. If the area of the window is 1 m2, and the ice is at -12 degrees Celsius, what is the minimum heat required to melt all the ice? Take the density of ice to be 900 kg/m3, the specific heat capacity of ice to be 0.5 cal/g*K, and the latent heat of fusion to be 80 cal/g. Answer in kcal.

12. Consider the titration of 0.100 L of 0.200 M ascorbic acid with 0.500 M NaOH. What is the pH at the endpoint of the titration? Enter your answer to two decimal places; for this question we can assume the 5% assumption is valid.

Determine the pH of each of the following solutions.

Part A) 0.25 M KCHO2

Part B) 0.15 M CH3NH3I

Part C) 0.22 M KI

A 5.65 −g sample of a weak acid with Ka=1.3×10−4 was combined with 4.80 mL of 5.90 M NaOH and the resulting solution was diluted to 750 mL. The measured pH of the solution was 4.25.

A student reacts 81g of salicylic acid with 14 mL of acetic anhydride producing 2g of acetyl salicylic acid. What is the percent yield of the reaction?

What mass of ammonium chloride should be added to 2.50 L of a 0.145 M NH3 in order to obtain a buffer with a pH of 9.65?