Answer / kang chuen tat (malaysia - pen

Answer 75 - (i) Number average molecular weight = Ma Xa + Mb Xb + Mc Xc = 14 x 0.5 + 16 x 0.3 + 18 x 0.2 = 15.4 kg / mol. (ii) Weight average molecular weight = (Ma Xa Ma + Mb Xb Mb + Mc Xc Mc) / (Ma Xa + Mb Xb + Mc Xc) = (14 x 0.5 x 14 + 16 x 0.3 x 16 + 18 x 0.2 x 18) / 15.4 = 15.558 kg / mol. (iii) Polydispersity = [ answer in (ii) ] / [ answer in (i) ] = 15.558 / 15.4 = 1.0103. (iv) Degree of polymerization = (Ma Xa + Mb Xb + Mc Xc) / (molecular weight of repeat unit) = (15.4 kg / mol) / (12 g / mol) = 1.283 k = 1283. The answer is given by Kang Chuen Tat; PO Box 6263, Dandenong, Victoria VIC 3175, Australia; SMS +61405421706; chuentat@hotmail.com; http://kangchuentat.wordpress.com.

ACCOUNTING AND FINANCIAL ENGINEERING - EXAMPLE 34.22 : An engineering company intends to produce a small piece of biochemical instrument for sales. Let A = overall fixed cost of production, B = variable cost of production per unit, C = selling price per unit, D = quantity of unit produced. Breakeven Analysis is used where revenue = cost. (a) Explain the role of Breakeven Analysis by using A, B, C and D. (b) Find the value of Contribution Margin in term of A, B, C and / or D. (c) At the breakeven point where revenue = cost, derive an equation of D as a function of A, B and C.

1 Answers  

---

Explain how can you estimate a gas flow based on two pressure measurements?

0 Answers  

---

Question 62 – The names of the flow streams could be represented by : H1 for first hot stream, H2 for second hot stream, C1 for first cold stream, C2 for second cold stream. Data of supply temperature Ts in degree Celsius : 150 for H1, 170 for H2, 30 for C1, 30 for C2. Data of target temperature Tt in degree Celsius : 50 for H1, 169 for H2, 150 for C1, 40 for C2. Data of heat capacity Cp in kW / degree Celsius : 3 for H1, 360 for H2, 3 for C1, 30 for C2. (a) Find the enthalpy changes, dH for all streams of flow H1, H2, C1 and C2 in the unit of kW. Take note of the formula dH = (Cp) (Tt - Ts). (b) Match the hot streams H1 and H2 with the suitable cold streams C1 and C2 to achieve the maximum energy efficiency.

1 Answers  

---

hi i am chemical engg. 4 year student i am not placed till year what will i do for my batter futere

3 Answers  

---

Question 75 - The molecular weights M in kg / mol of 3 different monomers a, b and c in a polymer are Ma = 14, Mb = 16 and Mc = 18. The fraction of polymer chain X of 3 different monomers a, b and c in a polymer are Xa = 0.5, Xb = 0.3 and Xc = 0.2. (i) Calculate number average molecular weight by using the formula Ma Xa + Mb Xb + Mc Xc. (ii) Calculate weight average molecular weight by using the formula (Ma Xa Ma + Mb Xb Mb + Mc Xc Mc) / (Ma Xa + Mb Xb + Mc Xc). (iii) Calculate the polydispersity by using the answer in (ii) divided by answer in (i). (iv) If the molecular weight of repeat unit is 12, calculate the degree of polymerization by using the formula (Ma Xa + Mb Xb + Mc Xc) / (molecular weight of repeat unit).

1 Answers  

---

How can one determine the particle size distribution for a given bulk solid?

0 Answers  

---

how to find a liquid flow's direction in a closed pipe by merely seeing it(without pressure gauges)...

4 Answers  

---

Hi, I am in need of interview questions from Engineers india limited in chemical engineering.if any one has kindly post it to me soon.

0 Answers   Halliburton, IOCL,

---

any meter avilable for measureing the Transformer Losses. ( like Voltmeter for voltage & ammiter for currenr )if yes plz give the make & supplier address, Email, Phone number.

0 Answers   Piramal Healthcare,

---

ACCOUNTING AND FINANCIAL ENGINEERING - EXAMPLE 34.27 : A biochemical engineering consultancy applies construction accounting in its finance. Its project began on 1 January 2010. Total revenue generated from the project was $9000. On 1 January 2011 as the budget, $2000 had been spent, with $6000 expected. However, the project cost increased latter, causing deviation from its initial budget on 1 January 2012, where $7000 had been spent, with $1400 expected. Let (estimated total cost) = (spent cost) + (expected cost to be spent), (percentage completion) = 100 (spent cost) / (estimated total costs), (total expected profits) = (total revenue) - (estimated total costs). Calculate : (a) total expected profits on 1 January 2011 and 1 January 2012; (b) estimated total cost as and not as the budget; (c) percentage completion of the project since the project began, in the first and second years.

1 Answers  

---

How to calculate the release flowrates from pressurized gas systems?

1 Answers   Reliance,

---

DIFFERENTIAL EQUATIONS - EXAMPLE 20.2 : During the landing process of an airplane, the velocity is constant at v. (a) If the displacement of the plane is x at time t, find the differential equation that relates t, x and v. (b) The plane has 2 parts of wheels - the front and the back, separated by a distance L. The front part of the wheel touches the land first, that allows the straight body of the plane to form an angle T with the horizontal land. If the vertical distance between the back part of the wheel and the horizontal land is y, find the equation of y as a function of L and T. (c) Find the differential equation that relates dy as a function of dt, v and sin T. (d) Find the differential equation that consist of dy as a function of y, L, v and dt. (e) Find the equation of y as a function of v, L, t and C where C is a constant. (f) When t = 0, prove that y = exp C as the initial value of y.

1 Answers  

---