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Health Policy Analysis- DNPC- 648 Week 3
$35.00Health Policy analysis-DNPC- 648
Discussion 3.1: Kingdon HP Model Framework
- Use the Kingdon HP Model Framework
- Address,‘Where do we go with the ACA in 2021?’
Discussion 3.2: Health Policy Rules and Regulations
- Use the https://www.congress.gov/site to search for health policy rules or regulations.
- Address, ‘How does the political climate effect the choice of health policy?’
The Path Forward
In your policy journal, create a new entry titled, ‘Post 3: The Path Forward‘ to address the following:
- Leverage the Brownson and Jones (2009) and Buerhaus (2017) readings assigned in this module.
- Draft a one-page policy brief that addresses how APRN Nurses will translate research into policy.
- Use the Health Policy Brief Tool to guide these sections:
- Preparation
- Executive summary
- Introduction
- Approaches and results
- Conclusion
- Implications and recommendations
- Review your draft using the success criteria on the Guided Checklist.
Use APA 7ed formatting and citations, as appropriate. Find Writing Support on the left navigation.
Step Three: Normative Values | Stakeholder Analysis
Continue to develop knowledge of and engagement with the health policy process that is related to your individual work using Seavey’s 2014 Health Policy Analysis seven-step framework; and to study the effect of policy on nursing practice, on patient health, and in health care.
For this assignment, Read Seavey’s 2014 Health Policy Analysis seven-step framework (Chapter 5) and complete a stakeholder analysis, addressing conflicts and barriers in your policy proposal. Identify the key stakeholders and what resources you will need to bring to the table. Organize your information utilizing the stakeholder impact matrix found in Chapter 5.
Draft a one- to two-page paper that addresses the following elements in the interactive process.
- Complete a stakeholder analysis.
- Clarify the conflicts and barriers in your policy proposal.
- Identify the key stakeholders and what resources.
- Include the stakeholder impact matrix found in this chapter.
Use APA 7ed and cite appropriately when needed. Find Writing Support on the left navigation.
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GINGER THERAPY (Zingiber officinale)
$20.00Complementary Alternative Medicine Project Guidelines
APNC 523 – Spring 2021
Complementary and Alternative Medicine
Evidence Based Practice Project
Alternative medicine is considered to be practices that are not used in conventional medicine. The science is constantly evolving and changing as determined whether treatments may or may not work or new discoveries are made. Complementary medicine is considered to be practices that are used in conjunction with conventional treatments. When these two are combined they are normally referred to as integrative medicine. Complementary and alternative medicines are becoming more and more prevalent. Approximately 40% of adults in the US use some form of CAM to either augment or replace conventional medical care. Others receive integrated care, for which there is some high-quality evidence of safety and effectiveness.
Complementary and alternative medicine involves several different therapies. For this project we will focus on Complementary alternative medications (i.e., dietary supplements, herbal remedies).
Evidence based practice is a problem-solving approach to clinical care that incorporates the conscientious use of current best evidence from well-designed studies. For this assignment, you will select a CAM “medication” – dietary supplement/herbal remedy from the sign-up list in class. Next, ask a question, and analyze some of the evidence that has been compiled surrounding your question.
Search the literature for relevant research. You should find at least 3 relevant research articles and/or studies that represent the best evidence which addresses your question. You should look for original sources, not just a secondary citation of someone else’s research. Research should include current primary sources from both the current bio-medical and social science literature (journals). The scientific evidence should be pertinent to your topic and discussion.
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Step 2: Complete the Academic Writing Sample
$10.00Step 2: Complete the Academic Writing Sample
Once you have completed the WRITE Course Tutorial above, you will compose a brief essay that demonstrates your academic-level writing skills and adherence to APA-style formatting requirements. Your writing sample must not exceed five pages in length, including the title page and reference page, and it must be submitted no later than September 21st. Your paper will be read and scored by your orientation instructor. If your paper does not reflect graduate-level writing skills and adherence to APA-style formatting requirements, you will work with our WRITE Program faculty to better prepare you for your courses.
Paper Overview: Use the APA-Format Template to compose an original, scholarly, APA-formatted paper on the topic of Robots in Health Care. Along with the popularity and adoption of technological conveniences in everyday life, robots and artificial intelligence are also being employed to assist patients in managing their health care needs. Examples of how robots are being utilized to assist patients include complying with medications, encouraging exercise, enhancing communication, and supporting activities of daily living.
Your paper will be scored using the following criteria:
- Paper Structure:organization, flow of thought, transitions, and format.
- Grammar and Writing Mechanics:grammar, punctuation, spelling, and sentence structure.
- Language:use of standard English vocabulary and tone.
- Content/Information:clarity of purpose, critical thought, and/or analysis of the topic.
- Adherence to APA Guidelines:document formatting (spacing, font, page set-up), references, citations, required document pages and sections.
Preparing to Write Your Paper
Read your choice of at least two of the journal articles below and at least one of the websites listed below. You may want to take notes on key points from the journal articles and websites. After you have completed these readings, write an outline using the five headings listed below. Once you have outlined your paper, you may begin writing. The paper must incorporate at least three references (i.e., two journal articles and one website), and your selected references must be cited within the paper in APA format. Note: Do NOT use additional resources when writing the paper. Use only the journal references listed below.
Journal Articles:
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- Robots and Service Innovation in Health Care
- Which Activities Threaten Independent Living of Elderly When Becoming Problematic: Inspiration for Meaningful Service Robot Functionality
- When Robots Care: Public Deliberations on How Technology and Humans May Support Independent Living for Older Adults
- Improving Therapeutic Outcomes in Autism Spectrum Disorders: Enhancing Social Communication and Sensory Processing Through the Use of Interactive Robots
- Friendship with a Robot: Children’s Perception of Similarity Between a Robot’s Physical and Virtual Embodiment that Supports Diabetes Self-Management
Web References:
- Robotics in healthcare – Get ready!from The Medical Futurist
- The future of medical roboticsfrom IT Pro Portal
- Top 6 Robotic Applications in Medicinefrom Alliance of Advanced BioMedical Engineering
Writing Your Paper
Your two pages of writing plus abstract must be free of grammatical and spelling errors. This is an original writing assignment, which means all factual data must be properly cited and referenced. Since your paper will be checked for originality, you must avoid even the appearance of plagiarism. In addition to your abstract and two pages of text, include an APA-formatted Title Page and Reference Page for a total of five pages. Your paper should be formatted as follows.
Page 1: Paper Title: The title of this paper is The Implications of Robots in Health Care.
Page 2: Abstract: A summary of your paper in 100 words or less.
Pages 3 & 4: The text of your paper
Headings are as follows (do not use additional headers):
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- Introduction (no header for introduction just use the title then your content for introduction)
- The Advantages of Robots in Health Care
- Where Robots Cannot Help with Health Care Needs
- Conclusions (based on the review of articles and websites; no personal opinions)
Page 5: References: List at least two journal articles and one website from the list of reading provided in this assignment.
Save your paper with the file name that uses your USD e-mail ID (without the @sandiego.edu) along with the title, Robots.
For example, John Doe’s USD e-mail is JDoe@sandiego.edu, so the file would be named JDoe-Robots
Click the assignment title link above to submit your writing sample for instructor review and feedback.
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Teamwork in continuous quality improvement (CQI)
$5.00After completing this week’s reading, you have learned that teamwork is an essential part of continuous quality improvement (CQI) and health care delivery. Health care professional roles include physicians, nurses, diagnostics (laboratory) and radiology staff, hospital administrators, patient registration, pharmacists, triage staff, and so forth. Each role has its own contribution to ensuring the delivery of quality care.
In your opinion,
- Discuss two of the roles listed above and their role in the delivery of quality care.
- Identify two professional responsibilities of the chosen roles, and link them to the quality improvement process of improving patient wait times in the emergency room.
- Include communication techniques this role would utilize to assist in improving patient wait times to the CQI team or staff.
Your initial post should be 250 to 300 words and utilize at least one scholarly source from the Ashford University Library to justify your statements. Cite all sources in APA format as outlined in the Ashford Writing Center’s video tutorial is available to help you become more familiar with the library database search features and how to generate keywords.
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Biopsychosocial Assessment And Treatment Plan
$10.00DEMOGRAPHIC DESCRIPTION: Identify and place client in his current reality situation including age, sex, race, ethnicity, religion, nationality, marital status, social class, sexual orientation etc.
PRESENTING PROBLEM: Include problem for which client seeks help. What is the source and reason for referral; whether problem is of recent origin or a long standing issue? What is client’s perception of problem? What precipitated the referral at this time? Is this client mandated and if so, what is the client’s response to this?
APPEARANCE: Describe physical appearance and any comments client makes about his appearance. Indicate if client description seems accurate.
LEVEL OF CONSCIOUSNESS: Describe level of alertness of the client; level of distraction; ability of client to stay connected to the worker. Did client seem sleepy, lethargic, drugged?
BEHAVIOR: Include quality, tone, and rate of speech. Include statement of any unusual movement and when occurred.
MOOD AND AFFECT: Describe mood and affect of client. Were mood and affect consonant? Were they consonant with content? What is the evidence of mood and affect?
THOUGHT CONTENT AND PERCEPTION: Describe the content of the client’s thoughts and perceptions. Indicate accuracy and appropriateness of them. Indicate whether there are any indications of hallucinations, delusions, suicidal or homicidal thinking. Are there any indications of thought disturbances such as thought broadcasting, thought withdrawal, thought insertion, ideas of reference, illusions or projections?
THOUGHT PROCESS: Describe the thinking process. Indicate whether the thinking includes magical thinking, blocking, self critical thinking, tangential thinking, echolalia, clanging, circumstantial thinking, loosening of associations, nonproductive thinking or flight of ideas.
INTELLECTUAL FUNCTIONING: Describe level of abstract thing or lack of this; describe ability to calculate numbers, how distractible is the person? Indicate if there is agnosia, apraxia, dementia or concrete thinking. How much schooling has the person had?
MEMORY SPHERES: Describe short and long term memory. Indicate if there is confabulation, word finding difficulties.
ORIENTATION: Awareness of self in person, place and time.
INSIGHT: Refers to level of awareness and understanding of the illness.
JUDGMENT: Ability to make good judgments, and pragmatic choices appropriate to protecting self and others.
IMPRESSIONS AND DIAGNOSTIC STATEMENT: Include the following:
Significant personal history of client
Assessment of client’s current social functioning in immediate social situations (family relationships, work, recreation, school etc.)
Assessment of personality structure of the client with particular reference to intellectual endowment, capacity for and quality of object relationships, tolerance for frustration and capacity to delay; capacity for reality testing; discuss interplay between client’s current reality situation and his/her ability (ego strengths and weaknesses) to deal with the situation. Discuss the nature and appropriateness of his/her defense mechanism in relation to the social factors and influences of current external pressures.
Assessment of the nature of the client’s problem in light of his/her history. Tie together the significant history and factors in cause-effect relationship as understood from the history. If the history does not contain sufficient information about a specific aspect, it is important to state that this is unclear, thus pointing out areas for further exploration and assessment.
HYPOTHESIZED DIAGNOSIS, PROGNOSIS AND RECOMMENDATIONS
16. Select 2 published articles that relate to your client’s issues. Summarize them in 2 short paragraphs. Cite them is APA 6th edition format. -
Histamines allergic reaction
$5.00Histamines
An allergic reaction prompts the body to produce histamines.
- Summarize the effects histamines can have on the body.
- What is the purpose of an antihistamine?
- Give at least 2 examples of an antihistamine.
- What functional groups are present?
- What are the benefits and dangers of using them?
- There are several books and articles that have been published regarding “Biblical Healing”. Find one of these articles or books and summarize it. Be sure to cite it as a source in APA format.
- Do you believe that an allergic reaction can be healed through faith alone? Does it mean you have weak faith if you do not?
Post your answers below and respond to at least two classmates’ posts with substantive responses.
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EXPERIMENT 3 Properties of Solutions- 2 day lab
$20.00EXPERIMENT 3 Properties of Solutions
Student Kit Materials:
Lab Kit:
Item Item # Price Electronic Pocket Scale, 100 x 0.01 g (already purchased) 3 x Pyrex® Screw-Cap Bacteriological Culture Tubes, 13 x 100 mm, 9 mL 731501 1.70 x 3 Graduated Cylinder, Polypropylene, 10 mL (already purchased) Safety Goggles 646706C 3.00 Beaker, 100 mL, 250 mL, 500 mL (already purchased) Student Responsibility:
Item Fine NaCl crystals Small Bowl (weighs less than 60 g) Coarse NaCl Crystals (Rock Salt) Coffee Mug Spoon Cooking Oil Iodine Tincture (Available at any drug store ~$4)- 1 oz. Isopropyl Alcohol (Rubbing Alcohol)- 16 oz. Mineral Oil- 16 oz bottle Table Sugar (Sucrose) EXPERIMENT 3
Properties of Solutions- 2 day lab
Materials: Solids: sodium chloride (NaCl) fine and coarse crystals, sucrose (table sugar, C12H22O11). Solutions: saturated sodium chloride (NaCl) and iodine tincture. Liquids: Cooking oil, mineral oil, isopropyl alcohol (rubbing alcohol) (C3H7OH).
Introduction
A solution is a homogeneous mixture in which one (or more) substance is dissolved in one or more other substances. For simplicity, we will investigate solutions consisting of one substance dissolved in one other substance. The solute is the substance that is dissolved. The solvent is the dissolving substance (also called the dissolving medium). The solvent is the substance present in the greater amount. The name of the solution is based on the name of the solute. In a “sodium chloride solution,” sodium chloride is the solute and water is the solvent.
A solution has a variable composition (ratio of solute to solvent) as more or less of the solute may be dissolved in a given amount of a solvent. A solution is a homogeneous mixture because the solute remains uniformly dispersed throughout the solution after mixing. In other words, there is only one phase.
Formation of a solution depends on the nature of the solute and the solvent. In general water, composed of polar molecules, is a good solvent for many ionic compounds which are composed of ions. Nonpolar solvents like benzene and hexane, composed of nonpolar molecules, are good solvents for other nonpolar compounds. The phrase in chemistry that captures the principle expressed in the preceding sentences is “Like dissolves like.” In other words, substances will dissolve other substances of similar polarity. In this experiment, we apply this principle to solids dissolved or not dissolved in liquids and liquids which are miscible or immiscible in other liquids.
The rate of dissolving a solute depends on:
- the particle size of the solute.
- whether the system is agitated (mixed) or not and how vigorously it is mixed.
- the temperature of the system.
- the concentration of the solute in the system.
The following terms are important:
Solubility is the amount of solute that will dissolve in a given amount of solvent at a given temperature. The terms used to describe solubility of a solid solute are: insoluble, slightly soluble, and soluble. When a liquid is added to another liquid, the term miscible is used to indicate that the liquid present in a lesser amount formed a homogeneous mixture with the liquid present in the greater. When the liquids form layers, the term immiscible is used.
Concentration of a solution may be expressed in words or mathematically as a ratio. It expresses the ratio of solute to solvent in a solution. The following word expressions are common and important to know:
Dilute solution: A solution that contains a small amount of solute per unit volume of solution.
Concentrated solution: A solution that contains a large amount of solute per unit volume of solution.
Saturated solution: A solution that contains the maximum amount of dissolved solute possible at a given temperature. In the laboratory, saturated solutions appear as homogeneous liquids on top of undissolved solid particles. The liquid, called a “supernatant liquid” because it is over (above) the undissolved solid, is in dynamic equilibrium with the undissolved solid.
Unsaturated solution: A solution containing less solute per unit volume than the corresponding saturated solution
Supersaturated solution: A solution that contains more dissolved solute than is normally present in the corresponding saturated solution at a given temperature. The supersaturated solution is not stable and will crystallize if the solution is disturbed.
The following mathematical expressions of concentration are important to know
Mass percent = x 100%
Molarity =
Procedure
- Concentration of a saturated solution (Plan ahead- this needs to set overnight)
- Preparation of the saturated NaCl solution: Weigh 36.6 g of fine NaCl crystals and place the crystals in a coffee mug. Add 100.0 mL of water to the mug. Place the mug in the microwave and heat the solution until it boils. Stir until all (or the great majority) of the crystals dissolve. Let the solution cool.
- Weigh a small bowl (needs to weigh no more than 50-60 g). Record the mass.
- Transfer 6 mL of the saturated NaCl solution to the bowl. Make sure to only transfer liquid- leave any solid residue behind. Weigh the bowl with the solution. Record the mass.
- Allow the bowl to set out overnight or until all the liquid has evaporated. Reweigh. Add water to the solid to dissolve it and dispose of it in the sink.
B. Relative solubility of a solute in two solvents
- Add 2mL of cooking oil and 2mL of water to a test tube, stopper it, and shake gently for 5 seconds. Allow the layers to separate and note which liquid has the greater density.
- Add 5mL of iodine tincture to the same test tube, note the color of each layer. Stopper and shake gently for 20 seconds. Allow the liquids to separate and note the color of each layer.
- Dispose of the mixture and clean the test tube.
C. Miscibility of liquids
- Take 3 dry test tubes and add liquids as follows:
- 1mL mineral oil and 1 mL isopropyl alcohol to test tube #1.
- 1mL mineral oil and 1 mL water to test tube #2.
- 1 mL water and 1 mL isopropyl alcohol to test tube #3.
- Stopper each test tube and shake for about 5 seconds. Note which pair is miscible.Dispose of waste in the designated container.
D. Effect of particle size on rate of dissolving
- Fill a dry test tube to about 0.5cm deep with fine crystals of sodium chloride. Fill another test tube to about the same depth (0.5cm) with coarse sodium chloride crystals.
- Add 10mL of tap water to each test tube and shake each tube. Note the number of seconds required to dissolve the salt in each test tube.
E. Effect of temperature on rate of dissolving
- Weigh two 0.5g samples of fine sodium chloride crystals.
- Add 50mL of cold tap water to a 100mL beaker. Add 50mL of boiling water to a 250mL beaker.
- Add the 0.5g of sodium chloride to each beaker and slowly tilt the solutions in each beaker. Observe how fast the sodium chloride dissolves in each solution. (Do not stir the solutions)
F. Solubility versus temperature; saturated and unsaturated solutions
- Label 4 weighing boats or papers as follows and weigh the stated amounts onto each one:
a- 1.0g NaCl b- 1.4g NaCl c- 1.0g Sucrose d- 1.4g Sucrose
- Place each 1.0g sample into a separate labeled test tube. Add 5mL of tap water to each, stopper, and shake until the solid in each test tube dissolves.
- Add 1.4g NaCl to the NaCl solution of part F.2. Add 1.4g Sucrose to the Sucrose solution of part F.2. Stopper and shake both test tubes. Note whether the crystals have dissolved in each.
- Place both unstoppered test tubes into a 500 mL Beaker with boiling water and stir frequently and vigorously, being careful not to break the bottom of the test tubes. Note results after 5 minutes. (You will need to continually add boiling water to the beaker so that the test tubes are consistently heated.)
- Cool the test tubes in running water for about a minute and let them stand for a few minutes. Record your observations.
Name__________________________
Section _______ Date _____________
Report for Experiment 11 Instructor_______________________
- Concentration of a saturated solution
- a- Mass of evaporating dish __________________
b- Mass of evaporating dish and saturated NaCl solution __________________
c- Mass of dish and NaCl after evaporation __________________
- Calculate: (Show work. For more space, use the reverse side.)
a- Mass of saturated NaCl solution __________________
b- Mass of NaCl dissolved in the solution __________________
c- Mass of water in the solution __________________
d- Mass % of NaCl in the solution __________________
e- Grams of NaCl per 100g of water __________________
- Relative solubility of a solute in two different solvents
- Which liquid is more dense, water or cooking oil? __________________
- What evidence supports your answer? ____________________________________
- What is the color of iodine in water? __________________
- What is the color of iodine in cooking oil? __________________
- In which solvent was iodine more soluble? __________________
- What is the experimental evidence? _____________________________________
_________________________________________________________________
- Miscibility of liquids
- Which liquid pair(s) tested is miscible? __________________
- How do you classify the water/mineral oil mixture? __________________
- Rate of dissolving versus particle size
- Time (seconds) required for fine salt to dissolve __________________
- Time (seconds) required for coarse salt to dissolve __________________
- What general conclusion can you draw?
_______________________________________________________________________
- Rate of dissolving versus temperature
- Did salt dissolve faster under hot or cold conditions? __________________
- Length of time (seconds) for salt to dissolve in hot water __________________
- Solubility Versus Temperature
- Which of the 1.0g solutions is saturated? __________________
- Evidence? _________________________________________________________
- Which of the 2.4g solutions is saturated? __________________
- Evidence?_________________________________________________________
- Which solid is least soluble at the elevated temperature? __________________
LAB EXERCISE 2 Name____________________________
Gas Laws
This week we covered gas laws in chapter 6. Please review this material and complete the following practice problems. Show all calculation setups, including units, for all problems.
- A sample of methane gas, CH4, occupies 3.25 L at temperature of 19.0 oC. If the pressure is held constant, what will be the temperature be if the volume expands to 10.00 L?
- A sample of oxygen gas occupies 1.9 L at pressure of 1156 torr. What volume will it occupy when the pressure is changed to 912 torr and temperature remains constant?
- The pressure of hydrogen gas in a constant volume cylinder is 5.01 atm at 21.0 oC. What will be the pressure if the temperature is raised to 70.0 oC?
- A 988 mL sample of air is at 852 mm Hg and 34.1 oC. What will the temperature of this gas be, in Fahrenheit, at 955 mm Hg and a volume of 602 mL?
- A sample of a gas occupies 9850 mL at STP. What volume will the gas occupy at 95 oC and 675 torr?
LAB EXERCISE 2 Name_____________________________
- A sample of nitrogen gas occupies 28.5 L at STP. How many moles of nitrogen are present?
- A 795.0 mL volume of hydrogen gas is collected at 23 oC and 1055 torr. What volume will it occupy at STP?
- What would the pressure be of 25.0 g of chlorine gas at –10.0 ºC in a 4.50 L container?
- Calculate the density of CH4 at STP.
- A volume of 495 mL of argon gas was collected at 21.0 oC and 779 torr. What does this sample weigh?
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Antiseptics and Oxidation
$5.00Antiseptics
In General, Organic, & Biological Chemistry read the Chapter 5.4 HealthLink titled, Antiseptics and Oxidation. Research an antiseptic of your choice.
- What antiseptic did you choose?
- Is it an oxidizing agent? How can you determine this?
- What is the main purpose of your antiseptic?
- What functional groups are present in the antiseptic?
- Define the terms germicide and bacteriostat? Classify your antiseptic in the appropriate category.
Post your answers below and respond to at least two classmates’ posts with substantive responses.
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EXPERIMENT 2 VSEPR- Structure and Shape
$25.00Valence Shell Electron Pair Repulsion Theory Lab VSEPR
Student Kit Materials:
Lab Kit:
Item
Item #
Price
Molymod® Individual Organic Pack
840172
13.00
Student Responsibility:
None
EXPERIMENT 2
VSEPR- Structure and Shape
Materials and Equipment: Molecular Model Kit.
Introduction
This exercise provides procedures to determine the structure and shape of molecules. This information is important because the properties of molecules are dependent upon their structure. The first step in determining the structure (Lewis structure) of a molecule is to draw a structure accurately showing the location of all valence electrons. From the Lewis structure, you can use a method called valence shell electron pair repulsion (VSEPR) theory to predict the shape of a molecule or ion.
In order to use VSEPR, you need to be able to determine the number of electron groups bonded to the central atom and the number of atoms bonded to the central atom. Lastly, after you have determined the molecule’s shape, you can determine whether electron density in the molecule is arranged symmetrically (a nonpolar molecule) or asymmetrically (a polar molecule). In a polar molecule, one end of the molecule has a partial positive charge, one end has a partial negative charge. The polarity of a molecule has important implications for the properties of molecules.
Theory of VSEPR
In order to use VSEPR, it is necessary to have a completed Lewis structure for the molecule. VSEPR is based on the principle that electron groups in a molecule tend to stay as far apart from each other as possible due to the repulsive forces that exist between like charges (the electrons). An electron group could be a lone pair of electrons, a single bond, a double bond or a triple bond around the central atom. The most probable arrangement of two, three, or four electron groups around a central atom are given in the table below. This arrangement allows groups to spread out as far as possible.
Table 1. Electron Group Geometries
# of Electron Groups Electron Group Geometry 2 Linear 3 trigonal planar 4 Tetrahedral As an example, let’s consider methane, CH4. The Lewis structure for methane is given below:
In this case we can see that there are four electron groups (4 single bonds) surrounding the carbon atom, hence the geometric arrangement of the electrons about the carbon atom is tetrahedral.
Ammonia, NH3, is a little more difficult.
The Lewis structure for ammonia shows that there are four electron groups (3 single bonds and 1 lone pair of electrons) therefore the electron group geometry is also tetrahedral. It should be noted however that CH4 has 4 atoms bonded to the central atom, while NH3 only has 3 atoms bonded to the central atom. Ammonia therefore they will not have the same shape as CH4. Molecular shape describes the arrangement of atoms about the central atom. When determining the molecular shape, you must consider the electron group geometry and the number of atoms bonded to the central atom. (Lone pairs are ignored at this point.) The possible combinations of electron groups and bonded atoms are summarized below.
Table 2. Electron Group Geometries and Molecular Shapes
# of Electron Groups # of Bonded Atoms Electron Group Geometry Molecular Shape 2 2 linear linear 3 2 trigonal planar bent (120°) 3 3 trigonal planar trigonal planar 4 2 tetrahedral bent (109.5°) 4 3 tetrahedral trigonal pyramidal 4 4 tetrahedral tetrahedral Using Table 2, we can predict that CH4 has a tetrahedral molecular shape while NH3 has a trigonal pyramidal molecular shape.
After the geometries have been assigned to a molecule, we decide if there is more than one correct structure for it. These correct structures are called resonance structures. Lastly, we can use the molecular shape to determine if electron density is evenly distributed across the molecule. If electron density is unevenly distributed across the molecule, the molecule is said to be polar. A molecule with a uniform charge distribution is nonpolar. But first you must learn how to draw Lewis dot structures…
Procedure
- Drawing Lewis structures. This procedure will be illustrated using SO2 as an example.
- Determine the total number of valence electrons in the molecule. The number of valence electrons from an atom can be calculated by its location in the periodic table. So, in this case, S and O are both in group VIA, so each atom contributes 6 electrons. Hence the total number of valence electrons in SO2 is 18 (3 atoms ´ 6 valence electrons).
For ions, it is necessary to add or subtract electrons depending on the charge of the ion. For anions, the magnitude of the charge should be added as additional valence electrons. For example, for OH– , the total number of valence electrons is eight: six from oxygen, one from hydrogen, and 1 for the negative charge (6 + 1 + 1 = 8). For cations, the magnitude of the charge should be subtracted from the number of valence electrons. For NO+, the total number of electrons is 10 (5 for nitrogen plus 6 for oxygen, and subtract one for the charge).
- Determine which atom is the central atom and place a pair of electrons between it and the other atoms. Generally, look for the atom that there is only one of in the formula. In SO2, there is only 1 sulfur atom (and 2 oxygen atoms) therefore sulfur is the central atom. Knowing this, we can construct the following crude sketch:
- Subtract the number of electrons used to connect the atoms from the total number of valence electrons. Remember each single bond is composed of 2 electrons. For SO2, 18 electrons (total) – 4 electrons (from the two bonds in step 1) = 14 electrons left over. Therefore we have 14 electrons left to place around the molecule.
- Add the appropriate number of electrons around each atom. Hydrogen requires 2 electrons, boron requires 6 electrons, and all other elements require 8 electrons. Start by placing electrons on the outer atoms to give them a compete octet. If more electrons are available, place them on the central atom. If the central atom lacks an octet, form multiple bonds with outer atoms (see below).
In our example, S and O both require 8 electrons. So first we put 6 electrons around one oxygen (which gives it 8 including the two in the bond) and another 6 electrons around the other oxygen. At this point our structure will look like this:
Now we have only two electrons left to place around the S atom. The question is, do we have enough electrons? If we place the two electrons around the S atom, sulfur will have only 6 electrons (as shown in the following structure), and we need 8.
We need to use the electrons more efficiently by making one of the lone pairs on an O atom a double bond. If we move a lone pair to make a double bond, we get the following structure.
This is the completed Lewis structure for SO2 because all of the atoms are surrounded by eight electrons (octet rule!). Remember an octet for hydrogen (H) is only two.
- Procedure to Determine the Electron Group and Molecular Shapes of a Molecule. The electron group geometry can be determined by counting the number of groups of electrons (atoms + lone pairs) around the central atom and then looking up the appropriate geometry in Table 1. In the case of SO2, we count three groups from the Lewis structure (2 atoms + 1 lone pair). From Table 1, the electron group geometry is trigonal planar.
The molecular shape can be determined by counting the number of atoms bonded to the central atom, and using the number of electron groups determined above to select the appropriate geometry from Table 2. SO2 has two bonded atoms and three electron pairs, so Table 2 indicates that the molecular shape is 120° bent.
- Resonance Structures. Some molecules have more than one correct Lewis structure. These are called resonance structures. In order for a molecule to have resonance structures, it must have at least one multiple bond. Molecules with only single bonds cannot have resonance structures.
In the case of SO2, the molecule has been drawn above with the double bond to the oxygen to the right of the sulfur. However, it could have also been drawn between the sulfur and the oxygen on the left, as shown below. These are the resonance structures for SO2.
- Polarity of a Molecule. The last piece of information to be obtained about a molecule concerns the distribution of electron density and charges around the molecule. A molecule with a uniform distribution of electron density is nonpolar; and one with an asymmetrical distribution is polar. A molecule is nonpolar only if it has no lone pair electrons about the central atom and all groups attached to the central atom are identical (both conditions must be met to be nonpolar). Another way to state this is if the electron group and molecular shapes are the same and the atoms attached to the central atom are identical, then the molecule is nonpolar.
In the case of SO2, the Lewis structure shows us that the molecule is polar because the sulfur atom has a lone pair.
Procedure
Determine the Lewis structure, electron group geometry, molecular shape, presence or absence of resonance structures, and the polarity for a series of molecules given on the worksheet. Once you have filled in the worksheet, build a model of each compound using your model kit. Compare the model you built with the responses you provided in the lab. Carbon tetrachloride is worked out for you as an example.
Names: Date:
CCl4 BF3 SO3 CO2 ClO2– Crude Sketch Calculations (# of valence electrons, # of bonds, etc. 1(4) + 4(7)=32 32-4(2) = 24
Lewis Structure # electron groups,electron group geometry 4tetrahedral # of bonded atoms, molecular shape 4tetrahedral Resonance structures (if any) none Polar or nonpolar nonpolar H2O SO42- NO2+ PO43- NO3– Crude Sketch Calculations (# of valence electrons, # of bonds, etc. Lewis Structure # electron groups,electron group geometry # of bonded atoms, molecular shape Resonance structures (if any) Polar or nonpolar CO32- SO2 NO2– PF3 SiI4 Crude Sketch Calculations (# of valence electrons, # of bonds, etc. Lewis Structure # electron groups,electron group geometry # of bonded atoms, molecular shape Resonance structures (if any) Polar or nonpolar NH3 H3O+ NH4+ SO32- CHCl3 Crude Sketch Calculations (# of valence electrons, # of bonds, etc. Lewis Structure # electron groups,electron group geometry # of bonded atoms, molecular shape Resonance structures (if any) Polar or nonpolar LAB EXERCISE 1 Name____________________________
Formulas and Names
- Complete the table below by providing the formula and name of the compound formed in the rectangle where the cation (positive ion) and anion (negative ion) intersect.
Cl– O 2- P 3-
Li+
LiCl
Lithium Chloride
Ca 2+
Cr3+
Mn 4+
LAB EXERCISE 1 Name______________________________
- Complete the table below by providing the formula and name of the compound formed in the rectangle where the cation (positive ion) and anion (negative ion) intersect.
NO3– CO3 2- PO4 3-
Na+
NaNO3
sodium nitrate
Pb2+
Fe 3+
Ti4+
LAB EXERCISE 1 (continued) Name______________________________
- Give the formulas for the following ionic compounds.
a- manganese (III) chloride _________________________________
b- magnesium sulfide _________________________________
c- barium bromide _________________________________
d- potassium phosphide _________________________________
e- cadmium acetate _________________________________
f- calcium permanganate _________________________________
g- cesium bromate _________________________________
h- beryllium dichromate _________________________________
i- ammonium peroxide _________________________________
j- iron (III) chloride _________________________________
k- uranium (V) sulfide _________________________________
l- nickel oxide _________________________________
m- tin (IV) nitride _________________________________
n- bismuth (III) hypochlorite _________________________________
o- mercury (I) thiocyanate _________________________________
LAB EXERCISE 1 (continued) Name______________________________
- Name the following ionic compounds.
a- BaI2 _________________________________
b- K3PO4 _________________________________
c- AlI3 _________________________________
d- Ag3N _________________________________
e- Li2Cr2O7 _________________________________
f- MnCO3 _________________________________
g- CsHCO3 _________________________________
h- Sr(BrO2)2 _________________________________
i- Li2CrO4 _________________________________
j- CrF6 _________________________________
k- TiO2 _________________________________
l- Co3P2 _________________________________
m- MnS2 _________________________________
n- Zn(OH)2 _________________________________
o- Ga(ClO)3 _________________________________
LAB EXERCISE 1 (continued) Name______________________________
- Name the following molecular compounds.
a- NF3 _________________________________
b- P2S5 _________________________________
c- SBr2 _________________________________
d- CO _________________________________
e- P4S3 _________________________________
f- SiI4 _________________________________
g- SCl6 _________________________________
h- OCl4 _________________________________
i- SeO2 _________________________________
j- N2O3 _________________________________
k- B2H6 _________________________________
l- AsI3 _________________________________
LAB EXERCISE 1 (continued) Name______________________________
- Give the formulas for the following molecular compounds.
a- nitrogen disulfide _________________________________
b- phosphorus pentabromide _________________________________
c- carbon tetrachloride _________________________________
d- sulfur hexabromide _________________________________
e- sulfur trioxide _________________________________
f- silicon disulfide _________________________________
g- diarsenic pentasulfide _________________________________
h- boron trichloride _________________________________
i- dinitrogen monoxide _________________________________
j- carbon tetrahydride _________________________________
LAB EXERCISE 1 (continued) Name______________________________
- For each acid, name the anion bonded to hydrogen, then name the acid.
Anion name Acid name
a- HI _______________________ _______________________
b- HCl _______________________ _______________________
c- H2S _______________________ _______________________
d- H3PO4 _______________________ _______________________
e- H3PO3 _______________________ _______________________
f- H2SO4 _______________________ _______________________
g- H2SO3 _______________________ _______________________
h- HClO4 _______________________ _______________________
i- HClO _______________________ _______________________
LAB EXERCISE 1 (continued) Name______________________________
- For each acid, give the formula of the anion bonded to hydrogen, then give the formula of the acid.
Anion formula Acid formula
a- hydrobromic acid ________________________ ________________________
b- hydrofluoric acid ________________________ ________________________
c- hydrocyanic acid ________________________ ________________________
d- nitric acid ________________________ ________________________
e- sulfuric acid ________________________ ________________________
f- periodic acid ________________________ ________________________
g- acetic acid ________________________ ________________________
h- sulfurous acid ________________________ ________________________
i- hypobromous acid ________________________ ________________________