Odesa

This page lists questions and answers that were posted by visitors named Odesa.

Questions

The following questions were asked by visitors named Odesa.

Name the following crystallographic features below using proper crystallographic notation. Image One [2ˉ21] [1ˉ12ˉ] [1ˉ1(1/2)] [(1/2)(1/2ˉ)1ˉ] Image 2 (1ˉ02) (21ˉ0) (201) (1ˉ02ˉ) The wrong answer as far I known in Image One:[(1/2)(1/2ˉ)1ˉ] Image 2:(1ˉ02)...

Metals yield at a stress much lower than those calculated on the basis of their bond strength alone. This is explained by the presence of defects. Identify the principal defects responsible for this observation. A)Grain Boundaries B)Interstitial Metal Ato...

The fictitious compound, arrhenium fluoride (AhF), reacts with itself to form a dimer with the formula Ah2F2. The reaction is second order in AhF. The value of the rate constant is 4.091×10−3 M−1s−1. What is the initial rate of reaction in a reactor fille...

Administratium bromide (AdBr) decomposes readily at temperatures exceeding 37°C. The figure below shows how the rate of reaction varies with the concentration of AdBr. The rate, r, is in units of M s-1 and the concentration of AdBr, c, is in units of M (m...

N2O5 dissolved in CCl4 decomposes to give N2O4 and O2. The reaction is first order with a half-life of 1234 seconds. How long will it take, in seconds, for the concentration of N2O5 to fall to 1.1% of its initial value?

H6P6: Urbium Oxide First Part of the Question: Urbium (Ur) is an upscale element found in big cities. Its oxide (UrO2) is not very stable and decomposes readily at temperatures exceeding 66∘ C. The figure below shows how the rate of reaction varies with t...

H6P7: Young's Modulus Rank the following 3 classes of materials in order of increasing typical Young's Modulus: metals such as copper, plastics such as HDPE (high density polyethelene), and ceramics such as alumina (Al2O3). Do not look up the values of Yo...

H6P8: Elongation A steel cable 10 m long is pulled in tension with a stress of 350 MPa. Assume that the Young's modulus of the steel cable is about 200 GPa. If only elastic deformation occurs, what is the resultant elongation in cm?

Here is the phase diagram of water with attention given to phases at high pressure. Name all phases present at the markers 1, 2 and 3. Phases present at 1: Liquid I II III IV V VI VII VIII IX Phases present at 2: Liquid I II III IV V VI VII VIII IX Phases...

Question One: Comment on the solubility of hydrogen ( H2 ) in liquid ammonia ( NH3 ). State whether you expect hydrogen to be highly soluble or almost insoluble, and explain why. i)Highly soluble due to hydrogen bonding. ii)Highly soluble due to compatibl...

Question One The fictitious compound, pandemonium fluoride ( PnF2 ) has a Ksp value in water of 3.091x10^-9 M^3 at room temperature. Calculate the solubility of PnF2 in water. Express your answer in units of molarity. Question Two How would you expect the...

Question One Lead chloride dissolves in water according to PbCl2(s)<-> Pb^2+ + 2Cl^- (aq) The solubility in pure water has been measured to be 4.44g . L^-1 . Calculate the solubility product of lead chloride in pure water. Your answer should be in units o...

(a) The phase diagram of the binary system, neodymium-scandium ( Nd-Sc ) is given below. There are two polymorphs in the solid state: alpha which is hexagonal close packed (HCP) and beta which is body-centered cubic (BCC). Identify all phases present at p...

The solubility of the fictitious compound, administratium fluoride ( AdF3 ) in water is 3.091x10^-4M . Calculate the value of the solubility product Ksp .

Answer the following questions by referring to the Cu-Al phase diagram shown below. (a) What is the lowest temperature at which a liquid can be found in a system of any composition of Cu-Al ? (b) A common alloy composition used in airplanes is 4 at. % Cu...

The fictitious compound, pandemonium carbonate Pn(CO3)2 hase a Ksp=3.091x10^-9M3 in water at room temperature. Calculate the solubility of Pn(CO3)2 in an aqueous solution of 1.11 M pandemonium sulfate Pn(SO4)2 (aq) . Express your answer in units of molari...

Consider the gold-platinum system which has a value of delta w of -4250 J/mole; (a) Calculate the enthalpy of mixing for a solution of 10% platinum and 90% gold. Express your answer in units of kJ/mole. (b) Is the dissolution of 10% platinum into gold an...

You wish to increase the carbon content of a slab of steel by exposing it to a carburizing atmosphere at elevated temperature. The carbon concentration in the steel before carburization is 193.5 ppm and is initially uniform through the thickness of the st...

(a) Cadmium telluride (CdTe) is a semiconductor witha band gap, Eg, of 1.45 eV. Calculate the value of the absorption edge of this material. Express your answer in meters. (b) Shown below are several % absorption vs. wavelength diagrams. Identify the corr...

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.31 kg m-3. Under these conditions the total surface area of the balloon is 0.11 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. C...

Show that a conventional x-ray generator is incapable of generating x-rays of wavelength as low as 10-11m. Do this by determining the identity of the target (in atomic number, Z) which would be needed to generate such x-rays.

(a) Identify the feature below using correct crystallographic notation. i) (2 1 0) ii) (^-1 1/2 0) iii) (^-2 0 1) iv) (2 ^-1 0) v) [2 1 0] vi)[^-1 1/2 0] vii) [^-2 0 1] viii) [2 ^-1 0] (b) Identify the feature below using correct crystallographic notation...

The glass panels of a sky roof need to be coated in order to screen out ultraviolet radiation (10-400 nm wavelength) but without color distortion in the visible spectrum. Candidate coating materials are gallium nitride (GaN) with a band gap,Eg, of 3.2 eV,...

The diffusion coefficient of silver (Ag) in copper (Cu) has the following values: T (K) D (m2s-1) 923 5.42 x 10-16 1173 1.34 x 10-13 (a) Calculate the activation energy for diffusion of silver in copper. Express your answer in units of J/mol. (b) You have...

You are conducting experiments with your x-ray diffractometer. (a) A specimen of molybdenum is exposed to a beam of monochromatic x-rays of wavelength set by the Kα line of silver. Calculate the value of the smallest Bragg angle, θhkl, at which you can ex...

Chemical analysis of a silicon crystal reveals gallium at a level of 3.091X10^-2 atomic percent. Assuming that the concentration of thermally excited charge carriers from the Si matrix is negligible, what is the density of free charge carriers (free carri...

How could one lower the glass transition temperature of a germate (GeO2) glass? Select all possible ways. i)Increase the cooling rate. ii)Decrease the cooling rate. iii)Add SiO2 to the glass melt. iv)Add CaO to the glass melt.

A formation energy of 1.11 eV is required to create a vacancy in a particular metal. At 777oC there is one vacancy for every 22,200 atoms. At what temperature will there be one vacancy for every 11,100 atoms?

The half-life of a first order reaction is determined to be 85.5 years. How long will it take for the concentration of the reactant to reach 2% of its initial value?

(a) The figure above shows how the energy of a system varies as a chemical reaction proceeds. Match the numbers features labeled on the figure above to their corresponding statements below: energy state of the reactants: 1/2/3/4/5 activation energy of the...

Answers

The following answers were posted by visitors named Odesa.

Free Surface Vacancies

qwerty and paul are right. Thank you both.

Thank you anonymous and Ibvda

For b) [1-2 2-] is which number? (i,ii,iii etc?)

Thank you Chemistry ;)

Odesa, the answer for b is VI) [1-2 2-] and thank you anonymous.

Thank you anonymous

Thank you Anonima

The answer 1.598e14 was not right for me too. Any ideas what happen and how to write it out?

The answer 9.31 is not right can any give a formula.

Thank you alex and babalovic for B)and anonim for A)

Thank you qwerty, Rufus for A)IV and Anonymous for B) VI

The answer 1.598e14 was not right for me too. Any ideas what happen and how to write it out?

Decrease the cooling rate. Add CaO to the glass melt.

a) 7.23 b) 475 ev

Answer is: 193000

(b) II Specimen A should allow silver to diffuse more quickly due to its smaller grain size and increased grain boundary area.

As its Si: 5.00*10^22 / (gallium level*10^-2) by someguy

Thank you someguy

Thank you someguy

Got the answer 297.622419061 hours.Thank you all for the advise, check through, and help, great way to make sure all of us don't use up our submissions. Again thank you bra, qwerty and yamy.

(6.023*10^23)/(12.05)=m m*(3.091*10^-8)*(10^-2)=

(6.023*10^23)/(12.05)=m m*(3.091*10^-8)*(10^-2)=

(6.023*10^23)/(12.05)=m m*(3.091*10^-7)*(10^-2)=

(6.023*10^23)/(12.05)=m m*(3.091*10^-8)*(10^-2)=

(6.023*10^23)/(12.05)=m m*(3.091*10^-8)*(10^-2)=

how do I believe you?

Step 1: (0.5* 6155.0 - 6155.0)/ ( 211.5 - 6155.0)= erf(ξ) Step 2: erf(ξ < 0.6), use the approximation erf ξ = ξ Step 3: t= d^2/4*D*ξ^2 d=59.0 x 10-2 cm D=3.091 x 10-7 cm2/s Step 4: t in sec -> hours Conversion seconds to hours is total/(60x60)

Step 1: ξ= (0.5 * carbon concentration at the surface of the steel - carbon concentration at the surface of the steel)/ (carbon concentration in the steel before carburization - carbon concentration at the surface of the steel) (0.5* 7345.0 - 7345.0)/ ( 2...

**We are here to help each other on this forum. Hope the info below helps'! Step 1: ξ= (0.5 * carbon concentration at the surface of the steel - carbon concentration at the surface of the steel)/ (carbon concentration in the steel before carburization - c...

Step 1: ξ= (0.5 * carbon concentration at the surface of the steel - carbon concentration at the surface of the steel)/ (carbon concentration in the steel before carburization - carbon concentration at the surface of the steel) (0.5* 6700.0 - 6700.0 )/ (...

Step 1: ξ= (0.5 * carbon concentration at the surface of the steel - carbon concentration at the surface of the steel)/ (carbon concentration in the steel before carburization - carbon concentration at the surface of the steel) (0.5* 8655.0 - 8655.0 )/ (...

74.5years X (multiply) with 5.64386

As its Si: 5.00*10^22 / (gallium level*10^-2) by someguy

Example:(remember to substitute with your data) Step 1: ξ= (0.5 * carbon concentration at the surface of the steel - carbon concentration at the surface of the steel)/ (carbon concentration in the steel before carburization - carbon concentration at the s...

Do you any idea to answer this question below, do give some input by providing data and how to with formula. A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.31 kg m-3. Under these conditions the total surface area o...

Thank you Anonymous and Anonima

a) stiff b) Addition polymerization c) 3.091×10^6 / 104.15 = 29678.34

a) Higher T b) Thermoplastic c) 5520

a) 4.27 x 10^-6 b) 536.7

a) 11.13 b) 10.76

a)vii:sp3d2 b)i:Slightly less than 90 c)4.13346*10^-7

a) 2.9844 b)K2O = basic Al(OH)3 = amphoteric Si(OH)4 = acidic CaO = basic

a)Addition Polymerization b)14286 c) iii) isotactic