The parabolic rate coefficient at 1200 °C wet oxidation is 0.920 μm²/hr. If it took 120 minutes to grow the initial oxide, for how long (in hours) should the wafer be subjected to another oxidation process to grow an 25000 Aº thick oxide?

If Vsu= Vorg, how many times should the extraction process be repeated in order for 1 g of substance with KD= 2.25 to pass 90.5% to the organic phase?

0.1 g of a zeolite adsorbs 5.58 cm³ of N2 gas at a pressure of 5.56 mbar, and 22.22 cm3 of N2 gas at 13.95 mbar. If the surface area covered by one molecule of nitrogen is 16 Å?, and a mole of gas occupies 22.4 x 103 cm3, calculate the zeolite surface area in cm? g-1.

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4. The %Mn in steel can also be determined spectrophotometrically by oxidizing the manganese to the intensely colored permanganate, MnO4-. Standard solutions of permanganate gave the following absorbances (in a 1 cm cell): ABSORBANCE CONC. OF MnO4 (g/mL) 0.210 1.05 x 10-5 0.315 1.61 x 10-5 0.429 2.21 x 10-5 0.599 2.98 x 10-5 0.801 4.04 x 10-5 The following samples of steel were thoroughly reacted to convert the manganese into permanganate and then diluted to 500.00 mL. WT. OF STEEL (g) ABSORBANCE 0.5886 0.611 0.3498 0.359 0.4555 0.482 Again using Excel, plot the calibration data and calculate the %Mn in the steel.

4.Why is there % error in APF cells? What could be the reason for such error? 5. By understanding the structure of crystals molecularly, what is its relation to the strength of materials? 6. Use the internet to search three (3) examples of metals which have HCP, FCC and BCC structures. Relate the structure to the characteristic properties of each metal. Please indicate the condition the given structures are observed.

(d) Calculate the electrical conductivity of a 6.0 mm diameter cylindrical silicon specimen of 60 mm long in which a current of 0.5 A passes in an axial direction. A voltage of 12.5 V is measured across two probes that are separated by 40 mm. i. Compute the electrical conductivity of the specimen. C12334 ii. Compute the resistance over the entire 60 mm of the specimen using the data in (1).

answer this very easy question

1) Name the applications of glass electrodes in potentiometric measurements (please write correctly and concisely).

What part does adsorption play in froth floatation for the concentration of sulphide ores and heterogeneous catalysis?