Question 1

2C2 H4 + 02 -- > 2C2 H40

Ethylene oxide is produced by the catalytic oxidation of ethylene. The feed into the reactor contains 1700 g/min ethylene and 3700 moles/min air.

a.      What is the limiting reactant?

b.      What is the extent of reaction if only 81% of the limiting reactant is converted to the product?

c.       What is the molar composition of the product stream?

Question 2

Air at 95 °F can hold maximum of 3.52 wt% water, defined as 100% humidity at 95°F. On a hot humid day the temperature is 95°F and the air contains 3.2 wt% water (90.9 % humidity). The air cooled to 68 °F because air at 68 °F can hold a maxium of 1.44 wt% water ( i.e 100% humidity at 68 °F), water condenses from the air. Hot humid air (95°F, 90.9% humidity) flows into a cooler at a rate of 154 .0 Kg/min. Calculate the flow rate of 2 streams leaving the cooler:

a.      Air at 68°F and 1OO% humidity (stream 1: air leaving the cooling unit)

b.      Water condensed from the air (stream 2: water leaving the cooling unit)

c.       What is the degree of freedom for the cooling unit

Question 3

A mixture of organic solvents containing 45.0 mole o/o xylene, 25.0o/o toluene, and the balance benzene (X) is fed to a distillation column. The bottom product contains 98.0 mole% xylene and no benzene, and 96.0°/o of the xylene in the feed is recovered in this stream. The overhead product is fed to a second distillation column. The overhead product from the second column contains 97.0o/o of the benzene in the feed to this column. The composition of this stream i 94.0 mole% benzene and the balance toulene.

a)      Draw and label a flow chart for the process

b)      Calculate the unknown process variables

c)      The percentage of the benzene in the process feed (i.e. the feed to the first column) that emerge ,in the overhead product from the second column.

d)      The percentage of toluene in the process feed that emerges in the bottom product from the second column.

If anybody can solve these questions I would rally appreciate it.

Discuss the fundamental principles, instrumentation, and analytical capabilities of thefollowing techniques:

•Potentiometry

•Cyclic voltammetry

•Anodic Stripping voltammetry

(b) Which technique is most selective for the determination of Calcium? Explain.

(c) Using a typical example, discuss the mechanism of ionization used in mass spectrometry

Acid/Base Equilibrium - Weak Acids/Bases

1. Estimate the initial [HClO] in an aqueous solution in which the [OCl^-] is 0.0000114 M at equilibrium (make an exact calculationassuming that initial concentration is not equal to the equilibrium concentration).

(Constant = K_a=3.50×10^-8)

HClO = OCl^- + H⁺

^{_________________ M}

3. Calculate the molar concentration of H⁺ ion of a 1.31×10^-2 M solution of the weak acid HClO (make an exact calculationassuming that initial concentration is not equal to the equilibrium concentration). Round your answer to 3 significant digits.

(Constant = K_a=3.50×10^-8)

HClO = OCl^- + H⁺

How many grams of dry NH4Cl need to be added to 2.20 L of a 0.600 M solution of ammonia, NH3, to prepare a buffer solution that has a pH of 8.50? Kb for ammonia is 1.8×10−5.

Calculate ? H for the reaction: C4H4(g) + 2 H2(g) — > C4H8(g) ? H = ?

Given,

C4H4(g) + 5 O2(g) — > 4 CO2(g) + 2 H2O(l) DH = -2341 kJ

C4H8(g) + 6 O2(g) — > 4 CO2(g) + 4 H2O(l) DH = -2755 kJ

H2(g) + ½ O2(g) — > H2O(l) DH = -286 kJ

Calculate the pH during the titration of 40.00 ml of 0.1000 M KOH with 0.1000 M HBr solution after the following additions of acid.

A) 29.00 ml
B) 39.00 ml
C) 48.00 ml

A 9.15-L container holds a mixture of two gases at 27 °C. The partial pressures of gas A and gas B, respectively, are 0.214 atm and 0.618 atm. If 0.210 mol of a third gas is added with no change in volume or temperature, what will the total pressure become?

Can the number and type of defects be varied and controlled? How? Explain the exponential variation of the concentration of defects with temperature. Explain each term of the equation in terms of their physical significance

Using Appendix 4 for ∆Hf ° and ΔS˚, which of the following reactions is spontaneous:

(5.a) 2 H₂S(g) + 3 O₂(g) → 2 H₂O(g) + 2 SO₂(g)

(5.b) SO₂(g) + H₂O₂(ℓ) → H₂SO₄(ℓ)

(5.c) S(g) + O₂(g) → SO₂(g)

You must determine whether a given reaction (i) is exothermic or endothermic, (ii) has a positive or negative entropy, and (iii) if a given reaction is spontaneous only at low temperature or only at high temperature, or at all temperatures.

Methyl methacrylate was polymerized at a mass concentration of 200g dm^-3 in toluene using azobisisobutyronitrile as initiator at a mass concentration of 1.64 X 10^-2 g dm^-3 and a reaction temperature of 60 degree C. Calculate the initial rate of polymerization and the molar mass of the poly(methyl methacrylate) formed in the initial stages of the reaction given that the relevant rate coefficients at 60 degrees C are:

Initiator dissociation: k sub d= 8.5 X 10 ^-6 reciproical seconds

Propagation k sub p= 8.33 dm^3 mol^-1 s^-1

termination, k sub t= 9.3 X 10 ^6 dm ^3 mol ^-1 s^-1

transfer to monomer k sub trm= 3.93 X 10 ^-3 dm^3mol^-1s^-1

Transfer to solvent k sub trS= 7.34 X 10 ^-3 d, ^3 mol ^-1 s^-1

Assume that the initiator efficiency f=0.7 that the termination by combinaition is negligible, and that the density of the initial solution of MMA in toluene is 860 g dm^-3

Use Coulomb's law to estimate the average distance between the sodium nucleus and the 3s electron.

1. Why is it not possible to reuse a heat pack in term of the chemistry?

2. Compare the specific heat of water to the specific heat of metal (Copper). Which would heat up faster (with less energy required)?

3. Why would metal make a poor ingredient in a heat pack?

4. If there was a delay between measuring the initial temperature of a hot object and its transfer to the calorimeter, how would the heat capacity of the object be affected? How would the calculation of the heat capacity of the calorimeter be affected (too high, too low, or no affect)?