Essay example --

Emotions and the physiological stress reaction can affect the everyday life? It is a way of expressing oneself in life. Positive emotions can open the door to learning for you. Negative emotions-especially overwhelming stress-can literally make to impossible to do well. This is subject that I know too well. The emotional state of mind also has a big part in our success. (Why Learning Is Not All in Your Head), Neurophysiologist Carla Hannaford writes: â€Å"Our mind/body system learns through experiencing life in context, in relationship to everything else, and it is our emotions, our feelings that mediate that context. In order to learn, think or create, learners must have an emotional commitment.† Becoming more aware on the state of mind a person is in makes a difference on how a person can be more proactive on a better quality of life. I’ve always want to be a better person too! I am challenged with many problems that makes performing my best difficult. We have to work to develop the right mindset and attitude that it takes in order to create the lifestyle that we all truly want. Change...

The Holocaust :: essays research papers

Hitler had a plan to ?purify? Germany in order to fulfill his vision of a perfect nation.In Mein Kampf, a book written by Adolf Hitler which explains his ambitions and explains how he wants to cleanse Germany of all Jews, communists, gypsies, homosexuals, and disabled people. Hitler had targeted specifically the Jewish population because of his hatred towards them. In World War Two, around 6 million Jews were persecuted by the Nazis. Firstly, in 1935, the Nazi Party passed the Nuremberg Laws, which were designed to stop Jews and Germans from marrying, to make sure that German blood was not tainted by mixing with other races, and produced pictures warning people about what could happen. People were ?warned? about which shop belonged to the Jews and were discouraged to buy any goods from Jewish stores. It was conspicuous that this racist law passed by Hitler was very degradingly towards the Jews. Despite that most people were not ignorant and knew this was wrong, no one dared to oppose the Nazis due to fear. Anyone that opposed the Nazis was to be shot. Hitler realized that this was not effective enough in order to achieve his goal. The Nazis had a meeting to discuss more efficient ways to eradicate the Jews. In 1938, the situation took a more serious turn for the worst. Called the night of Broken Glass, the Nazis started to use violence against the Jews. Jewish shops, churches, and other buildings were openly attacked. People became subjected to violence. It would lead to the start of more systematic violence. The violence escalated to the pinicle of the tragedy that the Jews experienced, the Holocaust. From 1939 onwards, Jews were rounded up. They were forced to move out of their homes. Jews started getting sent t o areas in cities designed only for them.

The work

The goal of MapleBear schools is to establish an enthusiasm for learning and knowledge in young children that will serve as a foundation for future uccess in the education system and in I Premium327 Words2 Pages Welcome Speech Welcome speech Good Evening/Afternoon everybody! I am extremely honoured to have the chance to address you in this prestigious moment when our institution, VC Kumaran Memorial School celebrates its 33rd Annual Day today. This is so precious moment for us because aside from the fact this funced each and every inch of this stage, be so hesitant to come up here and speak.What I am about to do is absolutely Premium978 Words4 Pages Farewell Welcome Speech â€Å"Goodbyes are hard. It may be harder for the person leaving, but it's always hardest or the one being left behind. † Welcome everyone to this special occasion. This event is bitter-sweet occasion. It is very sad to say good-bye to our classes 10-A and 11-C who are ending their remarkable J Premium284 Wo rds2 Pages School Speech Dear Principal, Teachers, Parent and children a very good evening to you all.It is my pleasure to be here today. Being invited to be the Chief Guest at the must be one of the high points of any parent's life. I was a student many years ago and indeed it's a great honour to be abl Premium313 Words2 Pages School Speech by Chief Guest Draft speech of Mrs. D. Purandeswari, MOS-HRD (HE) as Chief Guest on the occasion of the Annual Day of the Rainbow Concept School, Mahaboobnagar, A. P on 9th February, 2007 at 5. 30 p. m.It gives me immense pleasure to be here this evening and to address the young students of the Rainbow Concept Sc Premium1998 Words8 Pages School Day discover as the colours of cultural feast unfold ! Premium308 Words2 Pages Annual Sports Day My School Sports Day Games are compulsory in every school as physical development along with mental development is essential. All students are not necessarily good in studies. Some are good in sports. Much to the Joy of each students the Sports Day is one of the major events in the school.

Our Dreams

Each of us has many dreams and in fact they are a sign that we are alive, we exist and we are going forward despite the situation we live in. My dreams, like every young person, are countless. When we had midterm break my boyfriend fulfilled this long dream as a gift for Valentine's Day. We visited Venice and Bergamo. Our` hearts and souls are still there with the beauty that surrounds us. There everything is like in the movies I've seen with the difference that when you get up, you look around and realize you're part of the Italian breeze, your heart starts to beats as it wants to jump in order to enjoy beauty and intoxication with you. I'm still really excited even when I remember my experience. I can tell each destination separately for days. The one I chose to tell you is our last destination – Venice. The magic that conceals this magical place causes every visitor to yearn to return again and again there. The small, narrow streets have preserved the charm of the past times, bringing warmth, love and romance to tourists. I remember when we arrived at the boat at dusk. We went right in San Marco Square. The majesty of the basilica, pigeons and music of the symphony orchestras of every restaurant made everything in us dancing. We continued our tour around the island with a visit to all the sights, and for me The most beautiful place was the Bridge of Sighs. There I received my first Italian rose, which I keep to this day. The view provokes us a warm sigh and a desire to stop the time and to stay there forever. In the evening we were in a small restaurant at the Grande Canale, drinking red wine and enjoying the sunset. Love, Italy and Venice really go hand in hand. This country makes an unforgettable gift to every visitor by donating memories of eternal beauty, intoxication, romance and love. Once you have visited Italy, there is a warmth in your heart that keeps trembling and leaves the feeling that you have forgotten something and you have to go back and look for it.

Enlightenment World History Essay

The ideas of several Enlightenment philosophers, such as Locke, Montesquieu and Voltaire affected the latter U.S Constitution. Locke’s idea of how a government should be run affected the governmental power. Montesquieu’s idea of separation of powers affected the division of power of the U.S government. Voltaire’s idea of a person’s freedom affected the rights of the people. The ideas of Locke, Montesquieu and Voltaire greatly contributed to the creation of the U.S Constitution. Locke’s philosophy of how a government should be run affected the power of the government. According to Locke’s philosophy, a government’s power comes from the consent of the people. This idea was adapted in the Constitution and led to a limited governmental power, and the creation of a representative government. Locke’s idea was also applied in the beginning of the Constitution, where it says â€Å"We the people of the United States† because the statement established the idea of a government run by everyone and not just the people involved in the government.Locke’s idea led to a limited governmental power,the creation of a new government and the establishment of a government run by its people. Montesquieu’s idea of division of power in the government affected the federal system. Montesquieu believed in the concept that there should be a separation of powers which was later adapted by the delegates. The delegates set up a government where there were three separate branches which consisted of the legislative, executive and judicial branch. Another change that Montesquieu set forth was the built in system of checks and balances, which meant that every branch had the ability to check on each others actions. Montesquieu’s idea of separation of power helped contribute to the Constitution by leading to a government that equalized the power of its governmental leaders. Voltaire’s idea of a person’s freedom affected the written rights of a person in the Bill of Rights (the first ten amendments of the Constitution). According to Voltaire, a person should have freedom of speech and religion. This idea was the primary source of the Bill of Rights.When Congress wrote the Bill of Rights,freedom of speech and religion were guaranteed, along with other rights such as, freedom of press and assembly. Voltaire’s idea of a person’s right to choose their own religion and freedom of speech contributed to other essential freedoms that were previously not guaranteed by the U.S. Several Enlightenment philosophers such as Locke, Montesquieu and Voltaire contributed to the U.S Constitution. Locke’s idea of a government run by its people led to a re establishment of government. Montesquieu’s belief of separation of powers led to a new division of government. Voltaire’s idea of a person’s right of freedom of speech and religion led to more freedoms and rights guaranteed to a person. These are a few of the contributions made by several Enlightenment philosophers to the U.S Constitution.

Training & Development: a Tool of Retaining Employees

Training & Development: A tool of Retaining Employees â€Å"Abstract† NITIN GUPTA (ASST. PROF. IIMT HOTEL MANAGEMENT COLLEGE) The objective of this study is to show that training & development is required for an organization to retain its employees, as Training is activity leading to skilled behavior and it realize the employees that what they want in life& knowing how to reach it, where they want to go and how to get there, how high they want to rise and how to take off in the organization. The people in your organization are your most important resource. It is not only essential to hire the very best employees but the important is that a company retains those employees. Training and re-skilling inspire loyalty. Training is seen as expensive and a way of making their employees attractive to others. The risks involved, when weighed against the benefits, often mean that retraining is overlooked in favor of recruiting externally. However, the recruitment costs of staff time before and after the hire and direct expenses compare favorably against staff development costs. Training employees reinforces their sense of value. Through training, employers help employees achieve goals and ensure they have a solid understanding of their job requirements. A mixed approach of valuing staff by developing skills, providing interesting/motivating work while recognizing their individual contribution, along side benefits and perks, will mean that you are an employer that employees don't want to leave. TOPIC Training & Development: A tool of Retaining Employees INTRODUCTION The people in any organization are most important resource. It is not only essential to hire the very best employees but the important is that a company retains those employees. Training and re-skilling inspire loyalty. Training is seen as expensive and a way of making their employees attractive to others. The risks involved, when weighed against the benefits, often mean that retraining is overlooked in favor of recruiting externally. However, the recruitment costs of staff time before and after the hire and direct expenses compare favorably against staff development costs. Employees leave organizations for many reasons; oftentimes these reasons are unknown to their employers. Employers need to listen to employees’ needs and implement retention strategies to make employees feel valued and engaged in order to keep them. These retention methods can have a significant and positive impact on an organization’s turnover rate. According to strategic planning consultant Leigh Branham, SPHR, 88% of employees leave their jobs for reasons other than pay: However, 70% of managers think employees leave mainly for pay-related reasons. Branham says there are seven main reasons why employees leave a company: 1. Employees feel the job or workplace is not what they expected. 2. There is a mismatch between the job and person. 3. There is too little coaching and feedback. 4. There are too few growth and advancement opportunities. 5. Employees feel devalued and unrecognized. 6. Employees feel stress from overwork and have a work/life imbalance. 7. There is a loss of trust and confidence in senior leaders. WHY RETAINING EMPLOYEES IS IMPORTANT? Turnover is costly. According to Right Management, a talent and career management consulting firm, it costs nearly three times an employee’s salary to replace someone, which includes recruitment, severance, lost productivity, and lost opportunities. Life Work Solutions, a provider of staff retention and consulting services, provides the following turnover facts and rates: †¢ Over 50 % of people recruited in to an organization will leave within 2 years. †¢ One in four of new hires will leave within 6 months. †¢ Nearly 70% of organizations report that staff turnover has a negative financial impact due to the cost of recruiting, hiring, and training a replacement employee and the overtime work of current employees that’s required until the organization can fill the vacant position. Nearly 70 % of organizations report having difficulties in replacing staff. †¢ Approximately 50% of organizations experience regular problems with employee retention. From these statistics it’s clear that it’s important to develop a retention plan to retain employees and keep turnover low. If an employee resigns, then good amount of time is lost in hiring a new employee and then training him/her and this goes to t he loss of the company directly which many a times goes unnoticed. And even after this no one can assure the same efficiency from the new employee (He might be better and might not be). It requires time to judge his capabilities and work nature. And above all these things, one resignation many a times triggers a chain reaction among other employees, leading to a negative effect. RETENTION METHODS Here are some effective methods employers utilize in order to keep employees happy and part of their organization instead of looking for employment opportunities elsewhere. Training: Training employees reinforces their sense of value. Through training, employers help employees achieve goals and ensure they have a solid understanding of their job requirements. It’s important for companies to give coaching to employees so that their efforts stay aligned with the goals of the company and meet expectations. During an employee’s first few weeks on the job, an employer should provide intensive feedback. Employers should also provide formal and informal feedback to employees throughout the year. Mentoring. A mentoring program integrated with a goal-oriented feedback system provides a structured mechanism for developing strong relationships within an organization and is a solid foundation for employee retention and growth. With a mentoring program, an organization pairs someone more experienced in a discipline with someone less experienced in a similar area, with the goal to develop specific competencies, provide performance feedback, and design an individualized career development plan. Instill a positive culture. A company should establish a series of values as the basis for culture such as honesty, excellence, attitude, respect, and teamwork (IOMA, 2008). A company that creates the right culture will have an advantage when it comes to attracting and keeping good employees (Main). Use communication to build credibility. No matter what the size of the organization, communication is central to building and maintaining credibility. Many employers get communication to â€Å"flow up† through a staff advisory council (or similar group) which solicits and/or receives employees’ opinions and suggestions and passes them on to upper management (IOMA). It’s also important for employees to know that the employer is really listening and responds to (or otherwise acknowledges) employee input. Show appreciation via compensation and benefits. Offering things like competitive salaries, profit sharing, bonus programs, pension and health plans, paid time off, and tuition reimbursement sends a powerful message to employees about their importance at the organization. The rewards given to employees must be meaningful in order to impact their perception of the organization and therefore have a marked influence on its retention efforts. Moreover, if an organization promises a reward, it should keep that promise. Encourage referrals and recruit from within. Having current employees offer referrals could help minimize confusion of job expectations. Current employees can realistically describe a position and the environment to the individual he/she is referring. Another way an employer can lessen the impact of turnover is to hire from within, since current employees have already discovered that they are a good fit in the organization. Provide growth opportunities. An organization should provide workshops, software, or other tools to help employees increase their understanding of themselves and what they want from their careers and enhance their goal-setting efforts. It’s important to provide employees with adequate job challenges that will expand their knowledge in their field. According to Right Management, employees are more likely to stay engaged in their jobs and committed to an organization that makes investments in them and their career development. Make employees feel valued. Employees will go the extra mile if they feel responsible for the results of their work, have a sense of worth in their jobs, believe their jobs make good use of their skills, and receive recognition for their contributions. Employees should be rewarded at a high level to motivate even higher performance. The use of cash payouts could be used for on-the-spot recognition. These rewards have terrific motivational power, especially when given as soon as possible after the achievement. It’s important for employers to say â€Å"thank you† to employees for their efforts and find different ways to recognize them. Even something as simple as a free lunch can go a long way towards making employees feel valued. Listen to employees and ask for their input as to what rewards might work best at your organization. Conduct meetings and surveys to enable employees to share their input (Branham). Most team members will work harder to carry out a decision that they’ve helped to influence. Lower stress from overworking and create work/life balance. It’s important to match work/life benefits to the needs of employees. This could be in the form of offering nontraditional work schedules (such as a compressed work week, telecommuting, and flextime) or extra holidays. When work-life balance is structured properly, both the employee and employer come out ahead. For example, the employer will experience more productivity in the workplace because employees will be less stressed, healthier, and thus, more productive (Wingfield). Encouraging employees to set work/life goals, such as spending more time with their children, communicates that you really do want them to have a life outside of work and achieve a healthy work/life balance. Foster trust and confidence in senior leaders. Develop strong relationships with employees from the start to build trust. Employees have to believe that upper management is competent and that the organization will be successful. An employer has to be able to inspire this confidence and make decisions that reinforce it. An employer cannot say one thing and do another. For example, an employer shouldn’t talk about quality and then push employees to do more work in less time. In addition, employers need to engage and inspire employees by enacting policies that show they trust them, such as getting rid of authoritarian style of management. HOW TRAINING WORKS IN RETAINING EMPLOYEES? Once skilled workers are nestled within any organizations there is a second challenge in keeping them there – and here training and education can play a crucial role. Retaining good employees is critically important to a company's bottom line. Many companies that fail to place adequate emphasis on training make the mistake of assuming that pay is the only important motivating factor for their staff. In 1999 the Hay Group studied over 500,000 people in 300 companies to find out what promoted employee loyalty. The top three factors, mentioned by ninety percent of respondents, were; â€Å"career growth, learning and development†; â€Å"exciting work and challenge† and â€Å"meaningful work, making a difference and a contribution†. Fair pay and benefits was tenth on the list. After studying the above, following results are concluded as the output of training & development of employees: †¢ Optimum Utilization of Human Resources – Training and Development helps in optimizing the utilization of human resource that further helps the employee to achieve the organizational goals as well as their individual goals. †¢ Development of Human Resources – Training and Development helps to provide an opportunity and broad structure for the development of human resources’ technical and behavioral skills in an organization. It also helps the employees in attaining personal growth. Development of skills of employees – Training and Development helps in increasing the job knowledge and skills of employees at each level. It helps to expand the horizons of human intellect and an overall personality of the employees. †¢ Productivity – Training and Development helps in increasing the productivity of the employees that helps the organization further to achieve its long-term goal. †¢ Team spirit – Training and Development helps in inculcating the sense of team work, team spirit, and inter-team collaborations. It helps in inculcating the zeal to learn within the employees. Organization Culture – Training and Development helps to develop and improve the organizational health culture and effectiveness. It helps in creating the learning culture within the organization. †¢ Organization Climate – Training and Development helps building the positive perception and feeling about the organization. The employees get these feelings from leaders, subordinates, and peers. †¢ Quality – Training and Development helps in improving upon the quality of work and work-life. †¢ Healthy work environment – Training and Development helps in creating the healthy working environment. It helps to build good employee, relationship so that individual goals aligns with organizational goal. †¢ Health and Safety – Training and Development helps in improving the health and safety of the organization thus preventing obsolescence. †¢ Morale – Training and Development helps in improving the morale of the work force. †¢ Image – Training and Development helps in creating a better corporate image. †¢ Profitability – Training and Development leads to improved profitability and more positive attitudes towards profit orientation. †¢ Training and Development aids in organizational development i. . Organization gets more effective decision making and problem solving. It helps in understanding and carrying out organizational policies †¢ Training and Development helps in developing leadership skills, motivation, loyalty, better attitudes, and other aspects that successful workers and managers usually display. CONCLUSION Itâ⠂¬â„¢s clear that having proper retention strategies is key in order to retain employees. Productivity is maximized when employees enjoy their work. Offering opportunities to explore different options within the organization is one way of motivating the workforce. A company that is tuned into meeting employee needs should encourage movement across processes and functions. An environment that motivates and stimulates employees, managers need to incorporate motivation-building practices into their corporate culture. These practices include listening to employees and respecting their opinions, basing rewards on performance, and trained them to develop their skills & being available to them for everything from listening to their ideas and concerns to assisting them with their career advancement. Rotation of functions provides a forum for constant learning and self-improvement. When employees are given a chance to grow in various functions, a positive work environment is created. Thus, employee morale and productivity are maintained at a very high level. References/ Bibliography †¢ Crosscut magazine, spring 2002 (article by Iain Macdonald, Associate Director, Centre for Advanced Wood Processing) †¢ Harvard Business Essentials: Guide to Hiring and Keeping the Best People, Harvard Business Press by Sarah K. Yazinski, University of Scranton †¢ Training as important as salaries in staff loyalty By Gareth Morgan, IT Week Tuesday, July 31, 2001 02:59 PM Handle with care: motivating and retaining your employees   By Barbara A. Glanz Recruiting, training, and retaining new employees: managing the transition †¦ By Jack J. Phillips, Sharon L. Oswald Retaining your best employees: nine case studies from the real world of training  By Patricia Pulliam Phillips Web Page: http://writer4u. com Submitted By Leslie Wood

Melting Point Determination Essay

Identifying an unknown compound can be a difficult task. In identifying a compound, researchers often measure several physical properties: melting point, boiling point, density and observes a few chemical properties: reactivity, acidity, basicity of the compound. The reason for determining several chemical and physical properties of the compound is that it is quite possible for two different compounds to have a few physical and or chemical properties in common; but it is highly unlikely for the two compounds to have very many identical physical and chemical properties (Gilber & Martin, 2010). The goal of this experiment is to determine the identity of the unknown using the melting-point technique. If the entire compound in the list given by your instructor had distinctly different melting points, it would be possible to determine the identity of the unknown by just taking its melting point. However, each of the compounds in this list has a melting point that is close to the melting point of another compound in the list. Therefore, the melting point of the unknown will allow you to break down the choices to two compounds (Pavia, Lampman, & Kriza, 2013). To determine the identity of you compound, you must perform mixture melting points of your unknown and each of the two compounds with similar melting points. A mixture melting point that is depressed and has a wide range indicates that the two compounds in the mixture are different. It should be pointed out, however, that it is not possible to accurately predict the physical properties of newly synthesized or isolated compounds. Therefore, tables of physical properties are only useful in identifying previously known compounds. However, useful information as to the compound’s identity and its purity can often be obtained from its melting point. Although the melting point can be used to help identify an unknown by comparing its melting point to literature values, it must be apparent that there are literally hundreds if not thousands of compounds that share the same melting point. To solve this dilemma the identity of a compound can be confirm using mixed melting point method. If you prepare a mixture of you unknown chemical and the one you suspect it may be and measure the melting point of the mixture then there are two possible results: The melting point of the mixture is the same as the pure compound which means that the unknown compound and the known compound are the same. The melting point of the mixture is lower than either of the two pure components and the melting range is large. This is because the two compounds are different with the result that one is an impurity in the other (Dean, Jones, Holmes, & Reed, 2011). Determination of the temperature at which the solid and liquid phases of a substance are in equilibrium is time consuming. It is also quite difficult with a small amount of sample. Thus, in practice, most melting points are determined as capillary melting points, which can be done quickly with a small amount of sample in a capillary tube (Bettelheim & Frederick, 2004). Melting point analysis is a quick, relatively easy, and inexpensive preliminary analysis if the sample is already mostly pure and has a suspected identity. Additionally, analysis requires small samples only. As with any analysis, there are certain drawbacks to melting point analysis. If the sample is not solid, melting point analysis cannot be done. Also, analysis is destructive of the sample. For qualitative identification analysis, there are now more specific and accurate analyses that exist, although they are typically much more expensive. Also, samples with more than one solute cannot be analyzed quantitatively for purity (Molavi & Barron, 2011) Methodology: Finding an Identical Compound: Two melting-point capillaries were filled with small amounts of your sample. One was used to determine an approximate melting point range for your unknown by allowing the temperature to rise at about 6oC per minute. Then the melting point apparatus was cooled to at least 5oC below the temperature at which melting began. A slow, careful determination of the melting point range was made on the second sample by allowing the temperature to rise at a rate of approximately 2oC per minute. It is important that the melting point was measured carefully because finding another student in the lab with the identical compound depends on it. The melting point range was recorded in the laboratory notebook and also on the data sheet provided by the instructor along with the student number. From the data sheet, another student in the lab was located whose unknown has a melting point range that is within 4oC. A small amount of the student’s compound was used to prepare a sample for a mixed melting point. The error range of  ±4oC was accounted for experimental error and the fact that the thermometers are not calibrated thus the ranges from different instruments may vary slightly. To prepare the mixed melting point sample, one part of the unknown given was used to one part of the other student’s compound. The sample was mixed thoroughly by gently crushing the mixture with a glass stirring rod until it looks homogeneous. The melting point range was determined and the result was recorded in the laboratory notebook. Search was continued until you identified a student in the lab with a compound identical to yours and a second student in the lab with an unknown with approximately the same melting point range, but whose compound is not the same as yours. Results and Discussion: |Table 1 Mixed Melting Point Unknowns | |Unknown |Structure |Melting Point Range | | | |(oC) | |Benzoic Acid |[pic] |121-123 | |DL-malic Acid |[pic] |131-133 | |Urea |[pic] |132-135 | |Trans-cinnamic Acid |[pic] |131-136 | |Succinic Acid |[pic] |184 | Table 1 shows the given unknowns to be identified in this experiment. The melting point range in the table was the basis of the researchers in identifying their given unknowns. Some chemical compounds given from the manual was omitted to limit the scope of the experiment. Other books give different melting point range on the compounds in the table. This is because temperature also varies in the fact that the thermometers are not calibrated. The unknown pure compound has a white powdery solid feature. Melting point range determination is only applicable for solid compounds. Two trials were conducted to observe the melting point of the pure compound. For the first trial, it was observed that the compound starts to melt at exactly 135oC and the solid in the capillary tube was completely dissolved at 137oC. The solid melts instantaneously because the temperature of the cooking oil used arises rapidly compared when using water as a boiling bath. The second trial was conducted to confirm if the result for trial one is precise and the finding for the melting point also ranges from 135-137oC. From the data collected, it was predicted that the unknown might be urea or trans-cinnamic acid. Since both urea and trans-cinnamic acid have exactly the same melting point, it is difficult to determine which one is the given compound. The pure compound (Unknown A) was mixed to the compound (Unknown B) of one student with melting-point range of 134-136oC. Both unknown have the same physical feature which fell into conclusion that the two solids are same compounds. However, the temperature of the mixed compounds decreased by 80-84oC. Possible reason for this outcome is contamination of the mixed compound by the stirring rod used in mixing. Trial two was conducted for the mix-melting point determination. Another student whose compound (Unknown C) has a melting point that ranges from 131-134oC was mixed with Unknown A. Both unknowns have the same physical feature with Unknown B. The unknowns were mixed thoroughly with a clean stirring rod. The mixed compound starts to dissolve at exactly 134oC and solid in the capillary tube was completely dissolved at a temperature of 136oC. It is strong evidence that the two substances are the same. According to Mayo, Pike, and Forbes (2011), the crystalline lattice forces holding organic solids together are distributed over a relatively narrow energy range. The melting points of organic compounds, therefore, are usually relatively sharp, that is, less than 2oC. The range and maximum temperature of the melting point, however, are very sensitive to impurities. Small amounts of sample contamination by soluble impurities nearly always will result in meting-point depression. The drop in melting point is usually accompanied by an expansion of the melting-point range. Thus, in addition to the melting point acting as a useful guide in identification, it also can be a particularly effective indication of sample purity. The effectiveness of this technique depends on the relative solubility of the substances in each other. The usefulness of mixed melting points is limited in that you must have some idea of the chemical nature of your unknown compound and a sample of the suspected compound must be available. The researcher used melting points to determine the purity of organic compounds. Pure compounds were seen to have a narrow melting range, while impurities were seen to cause the melting range to become lower and broader. From the mixture melting points the researcher definitively able to identify the unknown as trans-cinnamic acid. 5. References: Aldrich, S. (n.d). Retrieved July14, 2013, from LLC, Sigma-Aldrich Co, http://www.sigmaaldrich.com/catalog/ product/aldrich/w228826?l ang=en ®ion=PH Bettelheim, Frederick, A., Landenberg, & Joseph M. (2004). Organic and Biochemistry (5th ed.). USA: A Division of Thomson Learning, Inc. Pages 17-20 Dean, J., Jones, M., Holmes, D., & Reed, R. (2011). Practical Skills in Chemistry (11th ed.). England: Pearson Education Limimited. Gilbert, J. & Martin S. (2010). Experimental Organic Chemistry: A Miniscale and Microscale Approach: A Miniscale and Microscale Approach (5th ed.). USA: Cengage Learning Mayo, D., Pike, R., & Forbes, D. (2011). Microscale Organic Laboratory with multistep and multiscale synthesis (5th ed.). United States: John Wiley & Sons, Inc. Molavi, S., & Barron, A. (2012, May 29). Melting Point Analysis. Retrieved from the Connexions Web site: http://cnx.org/content/m43565/1.1/ Pavia, D., Lampman, G., Kriz, G., and Engel, R. (2013). A Microscal Approach to Organic Laboratory Techniques (5th ed.). USA Cencage Learning.