3.AP Chem AB FRQ
Question 1
A sample consisting of 50. mL of 0.400 M solution of the acid, HClO4, is titrated
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titrated with a 0.200 M solution of the base, LiOH.
Write the balanced chemical reaction for neutralization reaction:
HClO4 (aq) + LiOH (aq) → LiClO4 (aq) + H2O (l)
Write the NET ionic equation for the neutralization reaction.
OH⁻ (aq) + H⁺ (aq) → H2O (l)
Compute the pH of the titration solution. Show your work
i) before any of the base is added
ii) after 25. mL of base is added
iii) after 50. mL of base is added
A student performs the titration with the same chemicals but with smaller volumes of each chemical . Which of the following titration curves could represent the titration. Explain
A because this entails a strong acid and a strong base.
Question 2
A student performs a titration of an unknown acid with a strong base and gets the following titration curve:
a) The student consults the list of pKa of acids shown below. If the acid is listed in the table below, which is the most likely identity of the unknown acid? Explain.
Acid
Ka
HF
7.2 x 10-4
CH3COOH
1.8 x 10-5
H2CO3
4.3 x 10-7
HBrO
2.0 x 10-9
The unknown acid is HBrO because the calculated Ka is in between 50^-4 and 50^-6 and 2.0 x 10^-9 lies in between them.
b) What is the initial molarity of the acid?
10^-3 = 0.001M
Question 3
a) Describe the components and the composition of an effective buffer solution. Explain how the components of the buffer allow the buffer to maintain its pH.
An effective buffer solution has a weak acid and its conjugate base or a weak base and its conjugate acid. A buffer solution is most effective when the ratio of its component concentrations is close to 1, also when the pH is equal to the pka of the acid.; The components of the buffer allow the buffer to maintain its pH because buffers can absorb excess H+ions or OH– ions.
An employer is interviewing four applicants for a job as a laboratory technician and asks each how to prepare a buffer solution with a pH of 5.0. The following constants may be helpful: hydrazoic acid, pKa = 4.74 Boric acid, pKa = 9.23
Archita A. says she would mix equal molar solutions of hydrazoic (HN3) and sodium azide (NaN3) solutions.
Bradley B. says she would mix equimolar Boric acid (H3BO3) and HCl solutions.
Carlos C. says he would mix equimolar Boric Acid (H3BO3) and sodium dihydrogen borate (NaH2BO3) solutions.
Delia D. says he would mix equimolar hydrazoic Acid (HN3) and NaOH solutions.
b) Which of these applicants has given an appropriate procedure? Explain your answer
Delia because she is using Sodium hydroxide which results in a pH of 5. NaOH is a strong base and in order to have an effective buffer a weak acid must be incorporated which is the HN3.
c) Explain what is wrong with the erroneous procedures.
The rest all incorporate a strong acid and a strong base or a weak acid and a weak base which don’ result in an effective buffer.
d) The applicants have access to the 1 Liter volumes of each of the solutions listed above. They have access to graduated cylinders. In order to make 1.0 Liter of the correct 5.0 buffer solution, what volumes of the two chemicals must be mixed?
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4.I am trying to figure out the optimal radius that will give the lowest surface area of a cylinder. I
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have done the calculus which reveals that the surface area is at a minimum when height is double the radius. I am now trying to find an equation for the relationship between the amount of wasted surface area as a percentage of the minimum surface area and the ratio between height and radius.
If I were to plot it on a graph, the y axis would be the percentage of excess materials needed as a percentage of the minimum possible surface area, and the x axis would be height divided by radius. Since the surface area is minimized when height=2(radius), I know that when x=2, y=0.
The website https://www.datagenetics.com/blog/august12014/index.html explains what I am trying to do quite well and shows the graph below. I am trying to find the equation for this graph, but am unsure how to go about it.
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6.A block of mass m1 lies on the horizontal plane, and another block of mass m2 is on it. A
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thrown through the system of pulleys shown in the figure. A load of mass M = m1 + m2 is suspended from the movable pulley. At what ratio between the masses m1 and m2 will the blocks not slide over each other if the coefficient of friction between the blocks is µ, and there is no friction between the lower block and the plane? The mass of the thread and pulleys, as well as the friction in the pulleys, should be neglected; the thread is considered unstretchable.
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9.Task 1
You are asked to carry out a study on behalf of a business analytics specialised consultancy on a subsample
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on a subsample of weekly data from Randall’s Supermarket, one of the biggest in the UK. Randall’s marketing management team wishes to identify trends and patterns in a sample of weekly data collected for a number of their loyalty cardholders during a 26-week period. The data includes information on the customers’ gender, age, shopping frequency per week and shopping basket price. Randall’s operates two different types of stores (convenient stores and superstores) but they also sell to customers via an online shopping platform. The collected data are from all three different types of stores. Finally, the data provides information on the consistency of the customer’s shopping basket regarding the type of products purchased. These can vary from value products, to brand as well as the supermarket’s own high-quality product series Randall’s Top. As a business analyst you are required to analyse those data, make any necessary modifications in order to determine whether for any single customer it is possible to predict the value of their shopping basket.
Randall’s marketing management team is only interested in identifying whether the spending of the potential customer will fall in one of three possible groups including:
• Low spender (shopping basket value of £25 or less)
• Medium Spender (shopping basket value between £25.01 and £70) and
• High spenders (shopping basket greater than £70)
For the purpose of your analysis you are provided with the data set Randall’s.xls. You have to decide, which method is appropriate to apply for the problem under consideration and undertake the necessary analysis. Once you have completed this analysis, write a report for the Randall’s marketing management team summarising your findings but also describing all necessary steps undertaken in the analysis. The manager is a competent business analyst himself/herself so the report can include technical terms, although you should not exceed five pages. Screenshots and supporting materials can be included in the appendix.
Requirements
After completing your analysis, you should submit a report that consists of two parts. Part A being a non-technical summary of your findings and Part B a detailed report of the analysis undertaken with more details.
Part A: A short report for the Head of Randall’s Marketing Management (20 per cent). This should briefly explain the aim of the project, a clear summary and justification of the methods considered as well as an overview of the results.
Although, the Head of Randall’s Marketing Management team who will receive this summary is a competent business analytics practitioner, the majority of the other team members have little knowledge of statistical modelling and want to know nothing about the technical and statistical underpinning of the techniques used in this analysis. This report should be no more than two sides of A4 including graphs, tables, etc. In this report you should include all the objectives of this analysis, summary of data and results as well as your recommendations (if any).
Part B: A technical report on the various stages of the analysis (80 per cent).
The analysis should be carried out using the range of analytics tools discussed:
• SPSS Statistics
Ensure that the exercise references:
• Binary and multinomial logistic regression
• Linear vs Logistic regression
• Logit Model with odds Ratio
• Co-efficients and Chi Squared
• MLR co-efficients
• Assessing usefulness of MLR model
• Interpreting a model
• Assessing over-all model fit with Psuedo R-Squared measures
• Classification accuracy (Hit Ratio)
• Wald Statistic
• Odd ratio exp(B)
• Ratio of the probability of an event happening vs not happening
• Ratio of the odds after a unit change in the predictor to the original odds
• Assumptions
• Residuals analysis
• Cook’s distance
• DfBeta
• Adequacy (with variance inflation factor VIF and tolerance statistic)
• Outliers and influential points cannot just be removed. We need to check them (typo? – unusual data?)
• Check for multicollinearity
• Parsimony
Write a short and concise report to explain the technical detail of what you have done for each step of the analysis.
The report should also cover the following information:
• Any type of analysis that might be useful and check whether the main assumptions behind the analyses do not hold or cannot be
• Give evidence of the understanding of the statistical tools that you are using. For example, comment on the model selection procedure and the coefficient interpretation, e.g. comment on the interpretation of the logistic regression coefficients if such a method is used and provide an example of
• Conclusions and explanation, in non-technical terms, of the main points
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10.I have written Argumentative Essay on Is love marriage better than arranged marriage? Can you proofread it and find any
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ead it and find any grammar or other mistakes? Can you also tell please that if this essay fits the criteria for being an argumentative essay and if it is a good argumentative essay? It is a 350 word essay and I can't cross the limit more.
Every relationship has its own importance. Marriage is a relationship, based on love or compromise, in which male and female interact and spend their life together. According to research, love and arranged marriage go hand-in-hand. Both are on the average scale because marriage has simply become part of business; however in modern era, the ratio of love marriage is increasing. Love marriages are considered superior because of understanding that both persons have for each other before marrying.
In love marriage, couples have mutual understanding. Despite facing numerous problems such as convincing parents to accept their choices and warding off false accusations and comments; however, these challenges guide them to happy life. In arranged marriages, both partners are unknown to each other and start their lives according to their parents' guidance. These couples don't make their own choices, but accept their parent’s demands. This leads to apathy for needs and feelings of their partner, which leads to weak bond between them.
In love marriages, couples always demonstrate respect to their partner's family members. They make many compromises to not hurt their partners; however, they still are able to speak frankly and openly. In arranged marriages, partners tend to speak with hesitation and tend to consider their own needs before those of their partner or partner's family.
In married life, couples should know what their partner prefer. This can only happen if the couple knows each other well before marrying. In arranged marriages, partners feel hesitation to share their feelings, likes, and dislikes; however, in love marriage partners already have an understanding of their partner's needs and just need to respect them and create a bond with their partner's family members. They care for each other's feelings and respect their boundaries.
In conclusion, arranged marriages are guided by parents whereas love marriages allow a couple the freedom to assess the future complexities that may arise in their lives. Love marriages contain mutual understanding that allows couples to solve their issues practically rather than emotionally. In a successful relationship, considering other person's feelings is a priority, which is commonly found in love marriages.
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12.Hello I have two problems to solve the subject is Quantitative Methods for Decision-Making
Problem 2
After graduating from AUD, Salman plans
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m 2
After graduating from AUD, Salman plans to start a book publishing company in the Media City. He did some research and found that the printer will cost Dh 230,000. He estimated that the variable cost per book is Dh 170 and the selling price is Dh 390.
a. How many books must he sell to break even? Also calculate the breakeven in dirham.
b. In addition to the costs given above, if he wants to pay himself a salary of Dh 15,400 per year, what is her breakeven point in units and dirham?
c. In the first three months of his business, he sold 400 books. Suddenly the printer breaks down. He spent Dh 25000 to fix the printer. In addition to 400 books sold, how many more books she should sell to breakeven? Assume that this part of the question is independent, and she does not draw any salary.
Problem 8
A furniture store makes tables and chairs from plywood and glass. The store has 30 units of plywood, 24 units of glass. Each table requires 7 units of plywood three units of glass, whereas each chair requires three units of plywood and two units of glass. The demand for chairs is between 2 and 4. The ratio between the table and chair is at least 1 to 2. A table earns $225 in profit and a chair, $145. The store also wants a minimum profit of $5000. The store wants to determine the number of tables and chairs to make in order to maximize profit. Formulate a linear programming model for this problem
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14.
Value: 1
equation image indicator
a. (x - 2)2(x - 3)2
b. (x2+ 4)(x2+ 9)
c. (x - 2)(x +
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2)(x - 3)(x + 3)
d. (x2 - 4)(x2+ 9)
Value: 1
The table below shows the cost of purchasing a standard stapler at five office supply stores, A through E. If the median cost of purchasing a standard stapler for these stores was $17.99, which of the following could NOT have been the cost of the stapler for Store A?
staplergraph.jpg
a. $19.95
b. $18.95
c. $16.95
d. $19.25
Value: 1
If equation image indicator then x =
a. 7
b. 1/5
c. 5
d. 1/7
Value: 1
A six−sided die, with sides numbered 1,2, 3,4,5, and 6, is tossed. What is the probability of tossing a number less than three?
a. 1/3
b. 0
c. 1/2
d. 1/4
Value: 1
If 6m + 4 = 8m, then 4m =
a. 6
b. 2
c. 8
d. 4
Value: 1
In the xy-plane, what is the y-intercept of the graph of the equation equation image indicator?
a. 2
b. 4
c. 16
d. There is no y-intercept.
Value: 1
Which of the following equations has both 2 and −4 as solutions?
a. x2 + 6x + 8 = 0
b. x2 - 2x - 8 = 0
c. x2 + 2x - 8 = 0
d. x2 - 2x + 8 = 0
Value: 1
The perimeter of a square is 20 ft. If you increase the length of the square by 2 feet and decrease the width by 1 foot, what is the area, in square feet, of the new figure?
a. 22
b. 28
c. 35
d. 40
Value: 1
(3x-2y4)-3 =
a. equation image indicator
b. equation image indicator
c. equation image indicator
d. equation image indicator
Value: 1
A softball is tossed into the air upward from a first floor balcony. The distance of the ball above the ground at any time is given by the function, distance function.png, where h(t) is the height of the softball above the ground (in feet) and t is the time (in seconds). What was the maximum height, in feet, of the softball above the ground after it was thrown?
a. 28
b. 30
c. 32
d. 34
Value: 1
A group of 100 people, some students and some faculty, attended a museum opening. Each student paid $10 per person for entrance to the museum and each of the faculty paid $25 per person for entrance. If the total paid, for all 100 people, was $1300, how many students attended the museum opening?
a. 20
b. 50
c. 70
d. 80
Value: 1
The ratio of Sam's age to Hank's age is 5 to 3. If the sum of their ages is 24, how old is Hank?
a. 21
b. 15
c. 19
d. 9
Value: 1
In the xy−coordinate plane shown below, point P has coordinates (8, −6). Which of the following is an equation of the line that contains points O and P?
O and P graph.jpg
a. equation image indicator
b. equation image indicator
c. equation image indicator
d. equation image indicator
Value: 1
The variables x and y are inversely proportional, and y = 2 when x = 3. What is the value of y when x = 9?
a. 54
b. 6
c. 2/3
d. 3/2
Value: 1
A farmer has 1235 trees to be planted on a rectangular parcel of land. If there are 24 trees planted in each row and each row must be complete before it is planted, how many trees will be left over after planting?
a. 21
b. 11
c. 0
d. 55
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