358 Words2 Pages

WMChemistry Pre lab for Experiment 2.9
In this lab you will calculate the percent yield. The percent yield is an indicator of the efficiency of a particular reaction. There are two factors that determine percent yield; actual yield and theoretical yield. The theoretical yield is the amount of product predicted from the amount of reactants used. This is similar to theoretical percent that you used to calculate the percent error in an experiment. The actual yield is the amount of product that is actually obtained in an experiment. This is similar to the actual or experimental percent you used to determine the percent error in an experiment.
The formula for percent yield is Actual yield x 100 Theoretical yield
For example: if a reaction actually gave you 6.63 g of nitrogen instead of the predicted 10.6 g, the percent yield of nitrogen would be:
6.63 g N2 x 100 = 62.5 % 10.6 g N2
1. According to her pre-lab stoichiometric calculations, a student’s lab experiment should have produced 5.51 g of NaCl. While actually doing the experiment, this student obtained only 4.32 g of NaCl. What was her percent yield?
2. A student calculated the theoretical yield of barium sulfate in a double replacement reaction experiment to be 1.35 g. When she filtered, dried and weighted her solid (precipitate), however, her yield was only 1.29 g. Calculate the student’s percent yield.
3. Before going to lab, a student reads in his lab manual that the percent yield for a difficult reaction to be studied was likely to be only 40% of the theoretical yield. The student’s pre-lab stoichiometric calculations predict that the theoretical yield should be 12.5 grams. What is the student’s actual yield likely to be?
4. Recall in a balanced chemical equation the coefficients represent the

Related

## Statistics Assignment Essay

991 Words | 4 Pages1. The researchers analyzed the data they collected as though it were at what level of measurement? a. Nominal b. Ordinal c. Interval/ratio d. Experimental 2. What was the mean posttest empowerment score for the control group? The mean/average posttest empowerment score for the control group was 97.12.

## Why Did You Choose This Particular Variable To Be Your Independent Variable?

732 Words | 3 Pages(the one you measure) * Why did you choose this particular variable to be your dependent variable? * Write any chemical equations involved? * What do you expect your results will show you in this investigation? * List of equipment you will use * What will you use to measure the independent variable? (the one you change) * What will you use to measure the dependent

## Intervention Strategy Essay

1056 Words | 5 PagesThis paper will summarize the article and Lu’s findings, describe the intervention strategy, and whether or not I would consider this type of strategy as an instructor of young children. Lu (2010) begins her study with observation in each of the classrooms of the three first grade students for a one week period. All three students were from middle socioeconomic families and although they were in separate classrooms with different teachers, each had been labeled as having “low motivation, little confidence, less engagement, were very restless, and were labeled with reading and writing disability “(p.2). Before beginning instruction with these students, Lu (2010) felt that much could be learned by interviewing the students and finding out their interests and preferred learning styles. From these interviews, she was able to obtain some basic information about the three students interests such as pets, friends, relatives, activities, vacations, celebrations, favorite television programs, and so forth.

## Lab Report Pka of Methyl Red

2236 Words | 9 PagesBy, solving the system of equations using linear algebra, the concentrations of the indicator and the conjugate base were determined. The Henderson-Hasselbach equation predicted that the pH for these solution plotted against the log of the ratio of the two species would yield a line whose Y-intercept equaled the pKa for methyl red. The value obtained was 4.96(1), which has a percent error of 1.9. Perhaps, if this were corrected for temperature there would be even greater agreement with the accepted value. INTRODUCTION The purpose of this experiment was to determine the pKa of an acid-base indicator (methyl red).

## Potasium Nitrate Essay

752 Words | 4 PagesThe moles of KNO3 s/ Kg solvent were needed to calculate the correct molal concentration. Another goal or purpose of this experiment was to calculate the heat of solution of each of the different concentrations. The inverse temperature and a linear plot of the molal concentration were needed to calculate this. The linear equation needed to calculate this was In(s)= -( H/ 2R)(1/T)+(1/2) where R is a constant and T was the temperature. The linear regression model could also be use to approximate the heat of solution.

## Rate of Absorbance in Catechol

1054 Words | 5 PagesI timed it in 20 second increments and noted the result in a spreadsheet. Materials and Methods Our group consist of myself, Lydia Huber, Erin and Ashley. The experiment was conducted in Cell Biology for Health Lab class on July 22, 2009. For comparison purposes and experience, prior to the experiment we conducted a similar experiment without the heating variable. This also allows us to become familiar with a machine familiar called the spectrophotometer.

## Kidblog Essay

455 Words | 2 PagesThere are three different classes so three different websites. We post our answers to the question given to us which nobody can see until the teacher checks them and then she posts it. The question we answered this time was “Who do you thing was most at fault regarding the red sweater?” After most of the class posted we collected data from this year and last year to analyze it and that is what we did. Many comparisons stand out when looking at the kidblog data. One comparison is the old and current thought that Rachel was least at fault old data with 5% out of 100% and current with 5% out of 100%.

## Organ. Behavior Tesyt Review

1001 Words | 5 PagesReview Test 8/20/13 7:23 PM BUS5450 - Organizational Behavior Term: Summer 2 2013 | Student Access: 7.1.2013 12:00 AM EDT - 8.25.2013 11:59 PM EDT | Section: 3 Test Review - Sarah White Your test grade is 95% The professor has configured this test to allow students to review: Questions answered incorrectly. Questions answered correctly. Students answers. Correct answers. QUESTION: 1 [QUESTION BANK ID: 20809] TYPE: TRUE FALSE CORRECT Giving good feedback can help “teach” new behavior: A B True False QUESTION: 2 [QUESTION BANK ID: 83509] TYPE: MULTIPLE CHOICE CORRECT Actions people take to try to control how others perceive them is called: A B C D Interdependence Interactional justice Impression management A diversionary tactic QUESTION: 3 [QUESTION BANK ID: 126243] TYPE: MULTIPLE CHOICE CORRECT An equivocal problem is one where: A B C D There are multiple subjective points of view about a solution All solutions are of equal value There is a single correct answer to solving it It is programmable QUESTION: 4 [QUESTION BANK ID: 10042] TYPE: MULTIPLE CHOICE https://grad.floridatechonline.com/Scripts/TestEngine/UserTest/ReviewTest.aspx?rid=936836&tid=833053&x=16-179 Page 1 of 5 Review Test 8/20/13 7:23 PM CORRECT Rude, discourteous behavior at work is called: A B C D Harassment Disruption Organizational citizenship behavior Incivility QUESTION: 5 [QUESTION BANK ID: 74953] TYPE: MULTIPLE CHOICE CORRECT Behavioral influences from rewards or punishments are: A B C D Classical conditioning.

## Illusion Effect on Muller-Lyer Illusion

2256 Words | 10 PagesIllusion effect on Muller-Lyer illusion Name: Yanlin Zhang Student ID: u4760310 Tutor’s name: Jo Lane Laboratory time: Tuesday 9-11am Abstract The study examines the proportion of trials participants choose the line which is the line without wings as bigger than the line with wings that using a within-subject design. The hypothesis is that the line with wings (the line with arrow tails) which was always 100 pixels long seems like longer than the line without wings. Participants were elementary psychology students from the course of Psychology 1003. The independent variable in this experiment was the length of the comparison line and the dependent variable was the proportion of the comparison line was longer than the Muller-Lyer line. Result from the study support the hypothesis and the line with wings (the line with arrow tails) which was always 100 pixels long seems like longer Illusory effect on Muller-Lyer illusion The most famous geometric illusion is the Muller-Lyer illusion.

## The Ability Of Eating Breakfast To Affect Your Gpa

495 Words | 2 PagesThe first question we asked was “what grade are you in,” which helped us figure out how much learning they have had. The second question was “what is your cumulative GPA,” which helped us know how well they do in school and what kind of grades they get. The third question was “how many school days a week do you eat breakfast,” is a well needed question to know if they regularly eat breakfast in the morning before school. The final question was “what gender are you,” which helped split up the subjects and create more data. Results We surveyed 53 students.

### Statistics Assignment Essay

991 Words | 4 Pages### Why Did You Choose This Particular Variable To Be Your Independent Variable?

732 Words | 3 Pages### Intervention Strategy Essay

1056 Words | 5 Pages### Lab Report Pka of Methyl Red

2236 Words | 9 Pages### Potasium Nitrate Essay

752 Words | 4 Pages### Rate of Absorbance in Catechol

1054 Words | 5 Pages### Kidblog Essay

455 Words | 2 Pages### Organ. Behavior Tesyt Review

1001 Words | 5 Pages### Illusion Effect on Muller-Lyer Illusion

2256 Words | 10 Pages### The Ability Of Eating Breakfast To Affect Your Gpa

495 Words | 2 Pages