Hot water was poured into an empty pop can and allowed to cool in surroundings whose temperature is 20 °C. The initial temperature of the water is 92 °C. After 12½ min the water temperature had dropped by 10 deg C. Assume the rate of change of the water temperature is directly proportional to the difference in the temperature between the water and its surroundings.

a. What is the value of the proportionality constant?

b. What is the temperature of the water after 83 min?

c. When is the rate of change of temperature at its largest?

d. When is the rate of change of temperature at its smallest?

What are the basic characteristics of a metal you need to know while selecting different meal and alloys for medical implant? What is difference between single crystal and polycrystalline metal? Why do you think reducing grain size is one of the strategies to strengthen a metal alloy? (4+2+4)

Using Excel matrix operations to balance the following equation

xC8H16 + yO2 --> zCO2 + tH2O

Question 1 Assuming Raoult's law to be valid for benzene (1)/ ethylbenzene (2), Prepare:

(a) A P-xy diagram (with at least 4 tie lines) for the temperature of 90o C

(b) x-y diagram for the temperature of 90o C

(c) T-xy (with at least 4 tie lines) for the pressure of 90 kPa

(d) x-y diagram for the pressure of 90 kPa

What are the typical major sources of carbon, nitrogen, and phosphorus in industrial fermentations for antibiotics?

For 2N₂O₅(g) = 4NO₂(g) + O₂(g)

1.  Determine, by making the appropriate graphs, whether this decomposition reaction is zero, first, or second order with respect to N2O5

I found by makin the graph in excel that it was a first order reaction

Now here are my questions

2. The stoichiometric coefficient for N205 in the reaction equation is 2. Depending on your answer to Problem 1, explain why the reaction order you obtained in Problem 1 is also 2, or explain why it can be different than 2?

3.Using the "Trendline" feature in the chart and the appropriate integrated rate equation, determine the rate constant for the reaction. (I have no idea how to even begin this in excel or on paper)

4. Sketch a graph showing the relative concentrations of N205, N02, and 02 as a function of time as the reaction proceeds. Your graph should show these concentrations on the same scale, and  should show the final concentrations relative to each other after equilibrium has been reached.  Note that the concentrations can be obtained just by considering the stoichiometry of the reaction. (Im not given the concentration of NO2 and O2)

Consider now a turbine(Q=0) that operates with N2 steam with T1 = 753.15K and P1 = 6 bar and P2 = 1 bar. The efficiency is 80% and the molar flowrate is (note not mass flow rate) is 200 mol/s. The inlet velocity is 30 m/s and the exit velocity is 120 m/s. The inlet is 6 m above the base of the turbine and the exit is 2 m above the base.  

a. Determine the output of the turbine with units.

b. what is the exhaust temperature and quality (if saturated) for 100% efficiency?

Calculate the following:

a. The bubble point temperature of a liquid mixture with a molar composition of 45.0 mol% n-hexane and 55.0 mol% n-heptane at 1.00 atm and the composition (mole fractions) of the vapor in equilibrium with this mixture.

Bubble Point:  _____°C

yHexane:  _____

yHeptane:  _____

b. The dew-point temperature of a gas mixture with a molar composition of 30.0% n-hexane, 35.0% n-heptane, and 35.0% air at 1.00 atm and the composition (mole fractions) of the liquid in equilibrium with this mixture.

Dew Point:  _____°C

xHexane:  _____

xHeptane:  _____

Determine the concentrations of all species in the exhaust from the complete and perfect combustion of an oil with the chemical formula C₁₆H₂₅S_0.1. Assume 51 % excess air (79 mol% N₂, 21 mol% O₂) is the source of oxygen.

A) Calculate the amount of oxygen in moles that must be supplied (includes excess).

B) Calculate the concentration of CO₂ in the exhaust gas in ppm.

C) Calculate the concentration of SO₂ in the exhaust gas in ppm.

How many meters of stairway (in height) could a 70 kg man climb if all the energy available in metabolizing an 11 g spoonful of sugar to carbon dioxide and water could be converted to work? For 1 mol of glucose oxidized to CO2 and H2O, 673 kcal of heat is released.

find solutions to the following using Excel's matrix operations?

A wastewater treatment plant has a rupture in one of their flow tubes, thereby leading to the discharge of waste material into a local lake system. The rupture goes unnoticed for a long enough time that the concentration of the waste in the lake reaches a steady state. Assume that the lake can be modeled as a continuously stirred tank reactor, with inflow, outflow, and complete mixing, and that the lake flows so that the volume remains constant at 107 m³. Pollutant-free water enters the lake at a volumetric flowrate of 45 m³/s. The waste from the wastewater treatment plant (that flows into the lake) has a waste concentration of 120 mg/L and a volumetric flowrate of 6 m³/s. Thus, there are two inlets to the lake, one with unpolluted water and the other with polluted water. The waste naturally decays according to the rate relationship, k*C_waste , where k = 0.15 day^-1. Determine the steady state concentration of waste in the lake, in units of mg/L (milligrams per liter). Express your answer to one decimal place.

You are working in a company that has developed a process to produce DNA vaccines from E. coli. After the fermentation step a lysis step is used to release the DNA from the cells resulting in a viscous mixture. You find that an aggressive cleaning solution heated to 80°C is required to clean the sticky mixture off the inside of the lysis tank. A countercurrent shell-and-tube heat exchanger containing 100 tubes is used to heat the cleaning solution from 10 C to 80°C at a mass flow rate of 8.6 kgs-1. The tubes have external and internal diameters of 11 mm and 10 mm, respectively, and a thermal conductivity of 17 W m-I K-I . Water enters the shell at 90°C at a mass flow rate of 22 kgs-1. The shell side heat transfer coefficient is 2500 W m­2 K-1

You are given the following data: The following correlation appliesfor turbulentflow in pipes: Nu = 0.023 Re^o.8 Pr^0.4 . Cleaning Solution: Thermal conductivity = 0.5 Wm-1 K-1 Viscosity = 1 x 10-3 Pa s Specific heat capacity = 3.68 kJ kg-l K 1 Density = 1,100 kg m­3 Water Specific heat capacity = 4.18 kJ kg-l KCalculate the surface area available inside the heat exchanger.

The purchased cost of a shell-and-tube heat exchanger (floating-head and carbon-steel tubes) with 100 m2 of heating surface was $4500 in 1990. What will be the 1990 purchased cost of a similar heat exchanger with 20 m2 of heating surface if the purchased cost capacity expo- nent is 0.60 for surface areas ranging from 10 to 40 m2? If the purchased cost capacity expo- nent for this type of exchanger is 0.81 for surface areas ranging from 40 to 200 m2, what will be the purchased cost of a heat exchanger with 100 m2 of heating surface in 2000?

An aqueous alkaline solution is 20 wt% NaOH and has a specific gravity of 1.222. It flows through a 5 inch diameter pipe at a rate of 20 gpm (gallons per minute).

A) What is the mean velocity of the solution in the pipe?

B) What is the mole fraction NaOH in the solution?

C) What is the molarity of NaOH in the solution?

D) The solution is for use in an oil refinery, where they like to use “barrels per day” for units of flow rate. What is the flow rate of the solution in barrels per day?