An aqueous solution containing 15% NaOH and 0.5% NaCl is concentrated at a rate of 100 kg/min in an evaporator. The concentrated solution is then mixed with 2000 kg of aqueous NaOH solution in a mixer. At the end of one hour a sample is collected from the mixer and analyzed. The analysis shows 40% NaOH and 0.8574% NaCl. Calculate the following: (a) The concentration of the original solution in the receiver (b) The composition of the concentrate from the evaporator (c) The mass of water in kilograms) evaporated in one hour

a) Consider a pressure of 15.75 kPa for the evaporation of the 50% NaOH solution. Determine the boiling temperature of the NaOH solution, determine the elevation of the boiling point of the solution with respect to the boiling point of water at the same pressure. b) Consider a pressure of 15.75 kPa for the evaporation of the 40% NaOH solution. Determine the boiling temperature of the NaOH solution, determine the elevation of the boiling point of the solution with respect to the boiling point of water at the same pressure. Based on your results, answer the following questions. Do you think what is an important parameter in the design of an evaporator? Why?

You wash a Coplin jar with soap and water to ensure it is clean before running a TLC. You should take the time to make sure there are no drops of water left inside the jar. (True or False)The solvent that the sample is dissolved in must always be the same as the eluant when running a TLC plate.(True or False)You are preparing to spot a sample of crude benzophenone and pure benzophenone on two separate lanes of a TLC plate to analyze the crude product. You can use the same TLC spotter for both samples.(True or False)After running a TLC plate to compare crude benzophenone and pure benzophenone you determine you need to prepare a new TLC plate and rerun the TLC. You can use the same spotter for the crude benzophenone as you did for the first TLC plate.(True or False)

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In the process of drying carrots using a parallel flow drying system, the material with a moisture content of 85% enters the drying system at a rate of 500 Kg / hour to produce dry carrots with a moisture content of 20%. If it is known that hot air used as the drying medium has a humidity ratio of 0.006 Kg of water per Kg of dry air and the flow of hot air enters the system at a rate of 200 Kg of air for each dry matter produced, calculate the ratio of humidity to air leaving the system assuming that the system is under steady state conditions.

One way to make coal “cleaner” is to gasify the coal into “city gas”. In a proposed molten-iron coal gasification process pulverized coal of up to 3 mm size is blown into a molten iron bath and oxygen and steam are blown in from the bottom of the vessel. Materials such as lime for settling the slag, or steam for batch cooling and hydrogen generation can be injected at the same time. The sulfur in the coal reacts with lime to form calcium sulfide, which dissolves into the slag. The process operates at atmospheric pressure and 1400 to 1500°C. Under these conditions, coal volatiles escape immediately and are cracked. The carbon conversion rate is said to be above 98% and the gas is typically 65 to 70% CO, 25 to 35% hydrogen, and less than 2% carbon dioxide. Sulfur content of the gas is less than 20 ppm. Assume that the product gas is 68% Co, 30% H2, and 2% CO2. Calculate the enthalpy change that occurs on the cooling of 1000 m3 of the gas at 1475 °C and 1 atm to 25°C and 1 atm.

You are given a 1.25 gram mixture of calcium nitrate and calcium chloride. You dissolve this mixture in 200.0 mL of water and add an excess of 0.300 M silver nitrate. You collect and dry the white precipitate which forms and find it has a mass of 0.325 grams. Calculate the percent calcium chloride by mass in the original mixture.

10. A container is separated into two halves by a membrane. Your lab partner assistant, Thurmond, is supposed to place a MgCl2 solution on side 1 and a NaCl solution on side 2. He is then supposed to measure the rate of water movement across the membrane. Unfortunately, Thurmond is not very good about keeping complete lab notes and he has forgotten to write down some data and calculations. Using your knowledge of osmosis, complete the following table. Temperature is 15°C and the hydraulic conductivity for the membrane is 0.4 ml/atm sec. MgCl2 Concentration on Side 1 NaCl Concentration on Side 2 80 mM Osmolarity on Side 1 Osmolarity on Side 2 Difference in osmotic pressure 60 mosM across the membrane Jy 0.95 ml/sec Reflection coefficient (ơ) Direction of water movement

Magnesium metal, a gray solid, is heated in a crucible in the presence of oxygen. A white powder is collected from the crucible. This is an example of A) a chemical change B) a separation C) a mixture D) a physical change

A rectifying column consists of a tube arranged vertically and supplied at the bottom with a mixture of benzene and toluene as vapor. At the top, a condenser returns some of the product as a reflux which flows in a thin film down the inner wall of the tube. At one point in the column, the vapor contains 60 mol% benzene and the adjacent liquid reflux contains 51 mol% benzene. The temperature at this point is 92°C. Assuming the diffusional resistance to vapor transfer to be equivalent to the diffusional resistance of a štagnant vapor layer 0.5 mm thick, calculate the rate of interchange of benzene and toluene between vapor and liquid. The molar latent heats of the two materials can be taken as equal. The vapour pressure of toluene at 92°C is 44.0 kN/m2 and the diffusivity of the vapors is 0.053 cm?/s.