Chemical Engineering homework help

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A propane / propylene mixture consists of 95% propane that has a flow rate of 1.31083 kg/s is initially at 54.44 °C. By inserting it in the shell side of a cross-flow shell and tube heat exchanger with one fluid unmixed. The heat exchanger has two shell passes. There are 3020 tubes each one has a diameter of 1.905 cm and 5.6388 m long, contains quenched water at a flow rate of 3.402 kg/s with an inlet temperature of 85 °C. The overall heat transfer coefficient “U” is equal to 8.5637 w/m^2 * c
Consider Cpc = 3.2387 J/kg*C , and Cph = 4.2 J/kg*C. (Assume the mixture has properties of propane). Calculate:
1- T out hot
2- T out cold
3- q
Use a solver with LMTD method (computer code in Matlab, or if you don’t know you can use Excel.). First, set your equations and assumptions and then use the solver.
extra information can be given upon request
“I have the code of the problem solved using NTU, but I need LMTD”

Chemical Engineering homework help

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A propane / propylene mixture consists of 95% propane that has a flow rate of 1.31083 kg/s is initially at 54.44 °C. By inserting it in the shell side of a cross-flow shell and tube heat exchanger with one fluid unmixed. The heat exchanger has two shell passes. There are 3020 tubes each one has a diameter of 1.905 cm and 5.6388 m long, contains quenched water at a flow rate of 3.402 kg/s with an inlet temperature of 85 °C. The overall heat transfer coefficient “U” is equal to 8.5637 w/m^2 * c
Consider Cpc = 3.2387 J/kg*C , and Cph = 4.2 J/kg*C. (Assume the mixture has properties of propane). Calculate:
1- T out hot
2- T out cold
3- q
Use a solver with LMTD method (computer code in Matlab, or if you don’t know you can use Excel.). First, set your equations and assumptions and then use the solver.
extra information can be given upon request
“I have the code of the problem solved using NTU, but I need LMTD”

Chemistry homework help

/in /by

It must include these categories: Octet rule, Lewis and VSEPR theory, valence bond and hybridization, and molecular orbitals.
Its due on Wednesday at 2:00 PM. It’s a project that requires information but it’s not hard, it’s for Chemistry 1.

Chemistry homework help

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It must include these categories: Octet rule, Lewis and VSEPR theory, valence bond and hybridization, and molecular orbitals.
Its due on Wednesday at 2:00 PM. It’s a project that requires information but it’s not hard, it’s for Chemistry 1.

Mass Spectrometry

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Mass Spectrometry
1)show the two (separate) possible fragmentation pathways that generate detectable
fragments of the molecule shown below. Hence, draw the structure of the fragments you
would expect in the mass spectra of this molecule.
2) the mass spectrum of an unknown alcohol (molecular formula= C5H12O) showed the
following data: M+ = 88 and fragments at m/ z=73,70, and 59
Determine the structure for the alcohol that fits this data. Hence show/explain how fragments
73, 70, and 59 are formed
3) what fragments are expected in the mass spectrum of the compound shown below? Clearly
draw the structure of the fragments
 
 
 
4) consider the compound shown below. Its mass spectrum shows base peak at m/z= 59. Show
(using equation) how the ion, that corresponds on this peak, is formed and hence draw the
structure of the ion.
5) assign compounds A and B to its correct mass spectrum. Clearly explain your answer

Chemistry homework help

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https://youtu.be/xHQM4B
Full Name:                                                                ID:
 
Experiment 5: Spectrophotometry of Colored Solutions Lab Report
Answer the Following Questions:

  1. List 3 components of a spectrophotometer, and mention the function of each of these components. (6 points)

 
 
 
 
 
 

  1. Violet light has an average wavelength of 410 nm, while red light has an average wavelength of 620 nm. Which light waves carry more energy in space? (1 point)

 
 
 
 
 

  1. A substance that is exposed to electromagnetic radiation can interact with it in one of three ways. List the three ways by which matter can interact with electromagnetic radiation. (3 points)

 
 
 
 
 
 

  1. A substance that is being measured for absorbance, displays a transmittance of 5% at 400 nm, and 50% at 600 nm. What is happening to the absorbance? (2 points)
    1. It is increasing.
    2. It is decreasing.

Explain your answer
 
 
 
 
 
 
 
 
 
 
Choose the correct answer and write the answers for any relevant questions briefly:
 

  1. Spectrophotometry is a technique that: (1 point)
    1. Measures the conductivity of a substance.
    2. Measures the color of a substance.
    3. Measures the interaction of light with a substance.
    4. Measures the quantity of light in an object.

 

  1. A substance that absorbs red light, is expected to have a __________. (1 point)
    1. Red color
    2. Black color
    3. Transparent property
    4. None of the above

 

  1. A substance that is placed first in the spectrophotometer as blank, sets the reading of the device to ________ and this is important to ___________. (1 point)
    1. 100% absorbance, minimize errors from impurities.
    2. 100% transmittance, minimize errors from impurities.
    3. 100% reflection, maximize the detection of sample.
    4. 100% transmittance, maximize the density of sample.

 

  1. What term describes the substance described in question 8? What is the most commonly used substance for that purpose? (2 points)

 
 
 

  1. A white object will absorb visible light at ___________. (1 point)
    1. 400 nm
    2. 600 nm
    3. From 400-600 nm
    4. None of the above

 
 
Bonus Question:

  1. A substance that absorbs light of wavelength of approximately 590 nm, will most probably have the color ____________.

Explain your answer. (2 points)

Chemistry homework help

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lab report
Deadline December 07,2020, 6:00 AM
Follow the Lab Report Guidelines to complete the lab report, including the data, statistical section, follow the templates of guidelines.

FST101A: Lab 9 Water Activity
Student Lab Report Guidelines
Fall 2020
Pay careful attention to the instructions. If you are unsure about what to do, contact any of the
TA’s for the course.
INTRODUCTION:
An introduction is the place in a manuscript where the reasoning behind an experiment is
introduced. It often contains a brief synopsis of what is currently known about the subject, which
segues into the purpose of the experiment and the hypothesis you had before performing the
experiment. Your hypothesis does not need to be correct – it just needs to be testable. You describe
whether your hypothesis was correct or not in the Discussion.
For this week, you will need to write a formal introduction in paragraph format. For the
introduction to this week’s laboratory report, answer each question full sentences, and then
organize into paragraphs that will constitute your introduction.
1. What is adsorption and de-absorption relative to moisture content?
2. What is the difference between water activity and moisture content?
3.
If you are a pathogen, is water content or water activity more important for your
survival?
4. Describe how to use water activity in the formulation of a product.
5. Describe some water activity regulations.
PURPOSE AND HYPOTHESIS
Based on your introduction, write the purpose of this lab. You can start the sentence with the
following: The purpose of this experiment is to ….. Remember that your introduction segues into
the purpose of the experiment.
Based on what is being tested in this lab, write a sentence describing what you think the outcome
will be. You can start the sentence with the following: I hypothesize that …..
METHODS:
Re-read the laboratory manual for the experiment this week. The manual provides you with a set
of instructions. A methods section is a description in sentences of what was actually done during
the experiment, such that someone could read it and be able to repeat what you did on their own.
The methods section contains the essential information for reproducing the results, but is not meant
to be an instruction manual. It is often helpful to break it up into sections.
In your statistical section of the methods, be sure to include one sample calculation for each of the
following:
• Initial sample weight
• Final sample weight
• Percent moisture final on a dry weight basis
• Percent moisture change on a dry weight basis
RESULTS:
Once you have made all of your Tables and Figures, remember to refer to them and describe them
to the reader in this section.
For this week, you need to create the following tables and figures for your report:
Tables:
1. Dish weight, initial + dish weight, and final + dish weight for potatoes for each salt used.
Please include the name and aw (water activity) for each salt. Also include the percent initial
moisture content for potatoes.
2. Dish weight, initial + dish weight, and final + dish weight for dog food for each salt used.
Please include the name and aw for each salt. Also include the percent initial moisture
content for dog food.
3. Calculated data for potato flakes: initial (wti), dry (wtd), final sample weights (wtf), and
percent moisture final (dry weight basis), and percent moisture change (dry weight basis).
Weights are the weight of the food- no dish!
4. Calculated data for dog food: initial (wti), dry (wtd), final sample weights (wtf), percent
moisture final (dry weight basis), and percent moisture change (dry weight basis). Weights
are the weight of the food- no dish!
Figures:
1. Percent moisture change vs aw for potato flakes. Make sure you take into account the
direction of change (i.e. + or -).
2. Percent moisture change vs. aw for dog food. Make sure you take into account the direction
of change (i.e. + or -).
When writing your results, be sure introduce and discuss each of the tables and figures and what
they are telling the reader (remember that the reader will not have observed the lab).
As you are making tables and writing about your results, remember to think about the number of
significant figures. Only use the number of significant figures appropriate for the measurement,
and make sure that you are consistent.
Also be sure to mention the reproducibility of the experiment.
DISCUSSION:
The discussion section is the section where you will interpret your results. For the Discussion for
this week’s laboratory report, use the questions below as a guide. The Discussion should be written
as paragraphs, and describe the results. The questions below are provided to guide you to thinking
about the data that was collected and its meaning. It might be helpful to answer each question first,
and then formulate your Discussion into meaningful paragraphs.
1. Why is the aw (water activity) of food important?
2. What is the difference between water content and water activity? Identify one limitation of
both measurements.
3. How is moisture content and water activity related?
4. What methods can be used to adjust the aw of a food?
5. How were the relative humidity of the salt chambers established? Discuss this in relation
to the water activities of each salt.
6. Discuss your results by comparing the dog food versus the potato flake samples. How were
they different? Specifically, explain reasons for your results based on the classification of
foods (i.e., dehydrated and intermediate moisture foods).
7. Discuss which salts gave moisture to each food and which removed moisture from the
foods, and explain whether the data yielded from the potato flakes and dog food could
correspond to an adsorption or desorption isotherm.
8. For dog food, estimate the initial aw from the graph of % moisture change vs aw (Figure 2).
(Hint: The estimated aw at which the % moisture change would be zero is an indication of
the initial aw of the food). Based on this value, discuss whether you would expect this
product to be stable against microbial growth.
9. Discuss advantages and disadvantages of this method for measuring moisture in foods. Is
this the industry standard?
10. What is the function of a humectant?
11. Explain and expand on water activity and pathogenic relationships. Include anecdotal
evidence.
12. Design an experiment to measure the impact of humectants on a product. (+/- controls)
13. You made relative humidity chambers for your food and added different salts and water to
them. Why did you add the salts first and the water last?
14. Replicates – discuss how reproducible this way of determining water activity is. Is there
another way to determine water activity?
15. Discuss the relationship of the environment in relation to the spoilage of food.

Chemistry homework help

/in /by

FST101A: Lab 9 Water Activity
Student Lab Report Guidelines
Fall 2020
Pay careful attention to the instructions. If you are unsure about what to do, contact any of the
TA’s for the course.
INTRODUCTION:
An introduction is the place in a manuscript where the reasoning behind an experiment is
introduced. It often contains a brief synopsis of what is currently known about the subject, which
segues into the purpose of the experiment and the hypothesis you had before performing the
experiment. Your hypothesis does not need to be correct – it just needs to be testable. You describe
whether your hypothesis was correct or not in the Discussion.
For this week, you will need to write a formal introduction in paragraph format. For the
introduction to this week’s laboratory report, answer each question full sentences, and then
organize into paragraphs that will constitute your introduction.
1. What is adsorption and de-absorption relative to moisture content?
2. What is the difference between water activity and moisture content?
3. If you are a pathogen, is water content or water activity more important for your
survival?
4. Describe how to use water activity in the formulation of a product.
5. Describe some water activity regulations.
PURPOSE AND HYPOTHESIS
Based on your introduction, write the purpose of this lab. You can start the sentence with the
following: The purpose of this experiment is to ….. Remember that your introduction segues into
the purpose of the experiment.
Based on what is being tested in this lab, write a sentence describing what you think the outcome
will be. You can start the sentence with the following: I hypothesize that …..
METHODS:
Re-read the laboratory manual for the experiment this week. The manual provides you with a set
of instructions. A methods section is a description in sentences of what was actually done during
the experiment, such that someone could read it and be able to repeat what you did on their own.
The methods section contains the essential information for reproducing the results, but is not meant
to be an instruction manual. It is often helpful to break it up into sections.
In your statistical section of the methods, be sure to include one sample calculation for each of the
following:
• Initial sample weight
• Final sample weight
• Percent moisture final on a dry weight basis
• Percent moisture change on a dry weight basis
RESULTS:
Once you have made all of your Tables and Figures, remember to refer to them and describe them
to the reader in this section.
For this week, you need to create the following tables and figures for your report:
Tables:
1. Dish weight, initial + dish weight, and final + dish weight for potatoes for each salt used.
Please include the name and aw (water activity) for each salt. Also include the percent initial
moisture content for potatoes.
2. Dish weight, initial + dish weight, and final + dish weight for dog food for each salt used.
Please include the name and aw for each salt. Also include the percent initial moisture
content for dog food.
3. Calculated data for potato flakes: initial (wti), dry (wtd), final sample weights (wtf), and
percent moisture final (dry weight basis), and percent moisture change (dry weight basis).
Weights are the weight of the food- no dish!
4. Calculated data for dog food: initial (wti), dry (wtd), final sample weights (wtf), percent
moisture final (dry weight basis), and percent moisture change (dry weight basis). Weights
are the weight of the food- no dish!
Figures:
1. Percent moisture change vs aw for potato flakes. Make sure you take into account the
direction of change (i.e. + or -).
2. Percent moisture change vs. aw for dog food. Make sure you take into account the direction
of change (i.e. + or -).
When writing your results, be sure introduce and discuss each of the tables and figures and what
they are telling the reader (remember that the reader will not have observed the lab).
As you are making tables and writing about your results, remember to think about the number of
significant figures. Only use the number of significant figures appropriate for the measurement,
and make sure that you are consistent.
Also be sure to mention the reproducibility of the experiment.
DISCUSSION:
The discussion section is the section where you will interpret your results. For the Discussion for
this week’s laboratory report, use the questions below as a guide. The Discussion should be written
as paragraphs, and describe the results. The questions below are provided to guide you to thinking
about the data that was collected and its meaning. It might be helpful to answer each question first,
and then formulate your Discussion into meaningful paragraphs.
1. Why is the aw (water activity) of food important?
2. What is the difference between water content and water activity? Identify one limitation of
both measurements.
3. How is moisture content and water activity related?
4. What methods can be used to adjust the aw of a food?
5. How were the relative humidity of the salt chambers established? Discuss this in relation
to the water activities of each salt.
6. Discuss your results by comparing the dog food versus the potato flake samples. How were
they different? Specifically, explain reasons for your results based on the classification of
foods (i.e., dehydrated and intermediate moisture foods).
7. Discuss which salts gave moisture to each food and which removed moisture from the
foods, and explain whether the data yielded from the potato flakes and dog food could
correspond to an adsorption or desorption isotherm.
8. For dog food, estimate the initial aw from the graph of % moisture change vs aw (Figure 2).
(Hint: The estimated aw at which the % moisture change would be zero is an indication of
the initial aw of the food). Based on this value, discuss whether you would expect this
product to be stable against microbial growth.
9. Discuss advantages and disadvantages of this method for measuring moisture in foods. Is
this the industry standard?
10. What is the function of a humectant?
11. Explain and expand on water activity and pathogenic relationships. Include anecdotal
evidence.
12. Design an experiment to measure the impact of humectants on a product. (+/- controls)
13. You made relative humidity chambers for your food and added different salts and water to
them. Why did you add the salts first and the water last?
14. Replicates – discuss how reproducible this way of determining water activity is. Is there
another way to determine water activity?
15. Discuss the relationship of the environment in relation to the spoilage of food.
DataforLab9 2020_Lab9_Water_Activity FST101AWeek9StudentGuidelines

Chemistry homework help

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PH 604                                                                                                                  NAME                                                                  
Homework 2                                                                                                      RED ID____________________________
 
 
The purpose of this assignment is to better understand the toxicity and exposure of certain chemicals. You will learn to collect important chemical information commonly used in EH.
 
Please write your answers in the document. After completing this homework, please save the document with the following name: HW2_YOUR Last Name_Date and then upload it to CANVAS.
 

  1. Health Effect (1 points):

 
 
Leukemia
Lung cancer
Skin cancera
Breast cancer
Intestinal cancer
Low birth weight
Preterm birth
Developmental effects – heart
Developmental effects – neurological
Low or absent sperm count
Other male reproductive toxicity
Autism
Birth defects (various)
Asthma
Wheeze
Type II diabetes
Hormonal alterations
Estrogenic effects
Kidney toxicity
Liver toxicity
Cataracts
Dermatitis
Skin conditions general
Chloracne (skin)
Immune system toxicity
Sensitization
Parkinsonism
Peripheral neurotoxicity
Neurological toxicity – other
Cholinesterase inhibition effects
Obesity
Heart attacks
Cardiotoxic effects
 
(other, write in with permission of instructor)
 
 
Please pick ONE health effect from the list below and write it here:_____________________________________________________________
 
1) List THREE chemicals (CAN BE A MIXTURE in some cases, such as tobacco smoke) that are associated with your particular health effect:THESE HAVE TO BE ENVIRONMENTAL CHEMICALS, NOT PHARMACEUTICALS (meaning something like arsenic, not a medicine like Prozac). Put chemical or mixture name, and CAS or RN for the chemical. Go to pubchemhttps://pubchem.ncbi.nlm.nih.gov/( 0.5 points each of the three below)
 
1.1.Chemical Name______________________________________________________
CAS or RN number __________________________________________________
 
1.2. Chemical Name _________________________________________________________
CAS or RN number __________________________________________________
 
1.3. Chemical Name _________________________________________________________
CAS or RN number __________________________________________________
 
2)Of the THREEchemicals you selected above, chooseONEand answer the following questions, using resources on pubchemhttps://pubchem.ncbi.nlm.nih.gov/as well as ATSDR Tox guides , if any https://www.atsdr.cdc.gov/toxguides/index.asp#B  and Tox Profiles https://www.atsdr.cdc.gov/toxprofiledocs/index.html
2.1 Selected chemical/ CAS #(0.5 points) ______________________________________________
Other names (no more than 3 here) ____________________________________
2.2 Of the ONEchemical selected, what is the Octanol-Water partition coefficient (log Kow) and if available, what is the Octanol-Air partition coefficient (LogKoa)? (0.5 points)
LogKow =
LogKoa =
2.3What are the main uses for this chemical? (0.5 point)
 
3)Why and how are people exposed? What are the main exposure routes?(0.5 points)
 
3.1If chemical is not in use today, is it still persistent in environment? (0.5 points)
 
3.2Is there significant exposure in the workplace or community/environment or both?(0.5 points)
 
4)Please list any health EFFECTS of CHRONIC exposure to this chemical  here  – UNLESS you are in the UNUSUAL situation of your chemical presenting an ACUTE health effect (explain) (usually chronic exposures are the issue in environmental health, but not always  – for example, carbon monoxide presents an acute health hazard(1 point)
 
4.1 As you may noticed, some chemicals have a lot information regarding their toxicity, based on the information you obtained, is this chemical a carcinogenic or teratogenic or mutagenic or a combination or none? (0.5 points)
 
4.1 What are the most common target organsonce this chemical is inside the body (shortly mention where it is distributed/accumulates) ? (1 point)
 
4.2 What is the LD50 of the selected chemical? Please note that some chemicals may have more than one LD50, depending on the organism (rats, mice, guinea pigs, rabbits, etc) or if it was injected, inhaled, ingested, dermal, etc. If more than one LD50 is found, please DO NOT list more than FIVE if more than one is available (1 point).
Homework2Instructions-1