PBH592 Final Examination Name:

Directions: Before you begin, save this form (FILE, SAVE AS: M8A2_Final Exam_Your First and Last Name). Read scenarios 1 – 8, and then answer questions 1—50. In order to receive full credit, you must copy and paste a screen captured image of your data output file from the statistical software that was used to compute the answer. To generate a screen capture image, press ALT + Prt Scr. Save your work frequently to your computer. Once you are ready to submit your work, click Browse My Computer and find your file. Once you’ve located your file click Open and, if successful, the file name will appear under the Attached files heading. Scroll to the bottom of the page, click Submit and you’re done. Be sure to check your work and correct any spelling or grammatical errors before you post.

Scenario 1:

General Questions- Answer the following multiple choice questions (1-10). Type out your answer in the space provided, include both the letter and the selection.

As the length of the confidence interval for the population mean increases, the degree of confidence in the interval’s actually containing the population mean_________________?

A Stay the same

B Increases

C Decreases

D Doubles

Answer: _______________

What value of a correlation coefficient indicates that there is a perfect positive relationship between the dependent variable, y, and the independent variable, x?

Answer: ___________

What value of a correlation coefficient indicates that there is no relationship between the dependent variable, y, and the independent variable, x?

Answer: ___________

For a fixed level of confidence when the sample size increases, the length of the confidence interval for a population mean will______________?

A Stay the same.

B Increase.

C Decrease.

D Doubles.

Answer: ___________

Which of the following confidence intervals will be the widest?

A 90 Percent.

B 95 Percent.

C 98 Percent.

D 80 Percent.

Answer: ___________

The probability of failing to detect an effect when one exists is known as a:

A Type II error.

B Type I error.

C Standard error.

D Standardized erro.r

Answer: ___________

Concluding that there is an effect when in reality no effect exists is known as a:

A Type II error.

B Type I error.

C Standard error.

B Type I error.

Answer: _________

As the sample size increases, how is the power of the study affected?

A It is not affected.

B It is decreased.

C It approaches zero.

D It is increased.

Answer: ___________

When a researcher decreases the risk of making a type 1 error, the risk of making a type II error is?

A Decreased.

B Not Affected.

C Increased.

D Equal to the chance of making a type I error.

Answer: ___________

The coefficient of determination

A helps establish causal relationships.

B indicates the amount of variance that two variables share.

C is the same as the correlation coefficient.

D is equivalent to standard deviation.

Answer: ___________

Scenario 2:

To determine the effectiveness of a new anti-hypothyroid drug, circulating thyroid stimulating hormone (TSH) levels were measured in 20 men (with hypothyroid levels) and compared to 20 men (with hypothyroid levels) that received current standard therapy as control. The data are summarized in the table below.

What is the null hypothesis equation for this experiment?

Answer: ___________

Based on the statistical test that you chose, do you accept or reject the null hypothesis at P=0.05?

Answer: ___________

What is the 95% confidence intervals for this 2 sample t-test?

Answer: ___________

What is the difference of Means?

Answer: ___________

What is the expected standard deviation (s) within groups?

s = “SEM Difference of means” /v(1/n+1/n) Round to the thousandths place.

Answer: ___________

What is the Power of this test? Please paste your data output file in the area below.

Answer: ___________

Assuming that the difference of means and expected standard deviation within groups remain the same, how many samples are needed to achieve a power of 0.80? Alpha=0.05.

Answer: ___________

Scenario 3.

An insurance company is interested in determining if the severity of a burn increases the length of hospitalization for burn patients. Their data is summarized in the table below.

Patient # Burn Severity

(Percent of body burnt x the degree of burn) Burn

Rank

Length of Hospital Stay (hours) Hospital Stay

Rank

1 1.33 1 74.1 2

2 1.25 2 74.2 1

3 1.22 3 73.5 3

4 1.11 4 72.5 4

5 1.1 5 72.1 5

6 0.99 6 58 6

7 0.95 7 56 7

8 0.88 8 48 8

9 0.8 9 38.1 9

10 0.7 10 32.2 10

11 0.56 11 28.2 11

12 0.4 12 25 12

13 0.35 13 24.5 13

14 0.32 14 24.6 14

15 0.3 15 24 15

What statistical test would be appropriate to establish a relationship between burn severity [Burn degree (1st degree, 2nd degree, and 3rd degree) x percent of body burned] and the duration of hospitalization expressed by the number of days?

A Pearson Product-Moment Correlation coefficient

B Multiple Regression

C ANOVA

D Spearman Rank Correlation coefficient.

Answer: ___________

What is the correlation coefficient?

Answer: ____________

Please paste your data output file in the space below.

Is the correlation positive or negative?

Answer: ___________

Scenario 4:

Have you noticed the abundance of television ads for yogurt that contain probiotics? Probiotics are live micro-organisms which, when administered in adequate amounts, confer a health bene?t on the host. Your body needs to have a healthy amount of ”good” bacteria in the digestive tract. Many yogurts are made using active, good bacteria. A diabetes researcher hypothesized that ratio good bacteria in the digestive tract would be decreased in people that are overweight. The results are summarized in the table below.

What type of statistical test would you use to determine if there is an association between the ratio of good bacteria and BMI?

Multiple linear Regression

ANOVA

Pearson Product-Moment Correlation Coefficient

Spearman Rank Correlation Coefficient

Answer: ___________

Do you accept or reject the null hypothesis that there is no relationship between BMI and the ratio of good bacteria in the digestive tract at the significance level P=0.05? Please paste your data output file in the space below.

Answer: ___________

Scenario 5:

The data in the following table show the relationship of cholesterol level in men to the risk of a heart attack. The data are summarized in the table below.

What is the slope and intercept of the regression line?

Answer: ___________

What type of statistical test would you use to determine if there is an association between cholesterol levels and the risk of a heart attack?

A Multiple linear Regression

B ANOVA

C Pearson Product-Moment Correlation Coefficient

D Spearman Rank Correlation Coefficient

Answer: ___________

Is the correlation positive or negative?

Answer: ___________

What is the correlation between cholesterol levels and the risk of suffering a heart attack?

Answer: ___________

What is the coefficient of determination for the value in the previous question? Round to the thousandths place.

Answer: ___________

Scenario 6

Suppose that you wanted to determine if a dietary supplement is effective at lowering blood pressure. You randomly select 200 people with slightly elevated blood pressure and give them either a placebo or the dietary supplement. Your research design is as follows in Table 1. You randomly select 100 people to receive the dietary supplement, and 100 people to receive the placebo. In order to determine the effectiveness of the dietary supplement, you measure systolic blood pressure. The drug was considered a success if it reduced blood pressure levels below 130 mm Hg. Your research hypothesis is: The dietary supplement will reduce blood pressure compared to placebo in people with moderately high blood pressure levels.

Table 1. Dietary Supplements and Lowering Blood Pressure

Blood pressure below 130mmHg Blood Pressure above 130 mm Hg

Placebo

n=100 20 people 80 people

Dietary Supplement

N=100 30 people 70 people

What is the null hypothesis equation for this experiment?

Answer: ___________

What proportion of people that received the placebo control had their blood pressure reduced at the end of the study?

Answer: ___________

What proportion of people that received the placebo control had their blood pressure reduced at the end of the study?

Answer: ___________

What statistical test would you use?

A 2 proportion z-test

B ANOVA

C Relative Risk

D 2 sample t-test

Answer: ___________

Based on the statistical test you chose, do you accept or reject the null hypothesis at P=0.05? Please paste your data output file in the area below.

Answer: ___________

What is the 95% confidence interval for this experiment?

Answer: ___________

What is the power of this statistical test? Please paste your data output file in the space below.

Answer: ___________

Assuming that the expected proportions remain the same for the two groups, how many samples are needed to achieve a power level of 0.80?

Answer: ___________

Which of the following statements is correct about why you would use the Yates continuity correction when performing a Power analysis?

A To increase your chances of making a type I error.

B To decrease your chances of making a type I error.

C To increase your chances of making a type II error.

D To decrease your chances of making a type II error.

Answer: ___________

Scenario 7

A research team wanted to determine if there is an association between an artificial sweetener and developing bladder cancer. They randomly selected individuals into the exposure group (Healthy individuals that consume artificial sweetener in diet soda; 1 L/day) and compare them to a randomly selected control group (Healthy individuals that do not consume artificial sweetener; 1L/day). They followed the subjects for a period of time 10 years. The data are summarized in the table below.

Table 2. Artificial Sweetener and Bladder Cancer

Developed Bladder Cancer Did Not Develop Bladder Cancer

Consume Artificial sweetener 75 325

Do Not Consume Artificial sweetener 50 350

What is the null hypothesis equation for this experiment?

Answer: ___________

What is the value of n for each group?

Answer: ___________

What statistical test would you use?

A 2 proportion z-test

B ANOVA

C Relative Risk

D 2 sample t-test

Answer: ___________ Risk

Based on the statistical test you chose, do you accept or reject the null hypothesis at P=0.05? Please paste your data output file in the area below

Answer: ___________

What is the 95% confidence interval for this experiment?

Answer: _____________

What is the power of this statistical test? Please paste your data output file in the area below

Answer: ___________

Assuming that the expected relative risk and expected proportion in unexposed controls remained the same, how many samples are needed to achieve a power level of 0.80? Please paste your data output file in the area below

Answer: ___________

Scenario 8:

Marijuana is the second most commonly smoked substance next to tobacco worldwide. With the recent legalization of marijuana in Colorado, a study was done to examine the relationships between chronic obstructive pulmonary disease (COPD) and smoking marijuana. Six hundred cases of males between the ages of 18 and 29 that reported to have smoked marijuana on their routinely on health physical examinations were cross matched for COPD. Six hundred age matched males were used as controls. The data are summarized in Table 3 below.

Table 3. Marijuana and Chronic Obstructive Pulmonary Disease

Develop chronic obstructive pulmonary disease (COPD) Do not Develop chronic obstructive pulmonary disease (COPD) Total

Smokes only Marijuana 81 519 600

Non smoker 58 542 600

What is the null hypothesis equation for this experiment?

Answer: _______________

What statistical test would you use?

A z-test

B ANOVA

C Relative Risk

D Odds ratio

Answer: _______________

Based on the statistical test you chose, do you accept or reject the null hypothesis at P=0.05? Please paste your data output file in the area below.

Answer: _______________

What is the 95% confidence interval for this experiment?

Answer: _______________

What is the expected proportion of controls for this experiment? Round to the thousandths place.

Answer: _______________

What is the power of this experiment? Please paste your data output file in the area below.

Answer: _______________

Assuming that the expected odds ratio and expected proportion in unexposed controls remained the same, how many samples are needed to achieve a power level of 0.80? Please paste your data output file in the area below.

Answer: _______________

11Name: ___________________________________ Date: ____________ Period: ________

Mass to Mass Stoichiometry

1. Carbon dioxide is produced in the reaction between calcium carbonate and hydrochloric acid.

a. Write the balanced equation for this reaction.

b. How many grams of calcium carbonate would be needed to react completely with 15.0g of hydrochloric acid?

c. How many grams of carbon dioxide would be produced in this reaction?

d. How many grams of calcium chloride would be formed at the same time?

2. Sulfur dioxide may be catalytically oxidized to sulfur trioxide.

a. Write the balanced equation for this reaction.

b. How many grams of sulfur dioxide could be converted by this process if 100.0g of oxygen are available for the oxidation?

3. Lightning discharges in the atmosphere catalyze the conversion of nitrogen to nitric oxide.

a. Write the balanced equation for this reaction.

b. How many grams of nitrogen would be required to make 25.0g of nitric oxide in this way?

4. Iron (III) oxide many be reduced to pure iron either with carbon monoxide or with coke (pure carbon). Suppose that 150.0kg of ferric oxide are available.

a. Write both balanced equations for this reaction.

b. How many kilograms of carbon monoxide would be required to reduce the oxide?

c. How many kilograms of coke would be needed?

d. In each case, how many kilograms of pure iron would be produced?

5. Zinc metal will react with either hydrochloric or sulfuric acid to produce hydrogen gas.

a. Write both balanced equations for this reaction.

b. If 50.0g of zinc are to be used in the reaction, how much HCl would be needed to completely react with all of the zinc?

c. If 50.0g of zinc are to be used in the reaction, how much H2SO4 would be needed to completely react with all of the zinc?

d. How much hydrogen gas (in grams) would be produced using HCl?

e. How much hydrogen gas (in grams) would be produced using H2SO4?

6. Calcium phosphate, silicon dioxide, and coke may be heated together in an electric furnace to produce phosphorus, as shown in the following equation.

2Ca3(PO4)2 + 6SiO2 + 10C ? 6CaSiO3 + 10 CO + P4

a. In this reaction, how many kilograms of calcium phosphate would be needed to make 100.0kg of phosphorus?

b. How much calcium silicate would be formed as a by-product?

c. How much sand would be used up in this same reaction?

7. Phosphoric acid is produced in the reaction between calcium phosphate and sulfuric acid.

a. Write the balanced equation for this reaction.

b. How much of the phosphoric acid would be produced from 55g of the calcium phosphate?

c. What other product is formed?

d. In what quantity is the other product produced?

8. Phosphine, PH3, is formed when calcium phosphide is added to water.

a. Write the balanced equation for this reaction.

b. How many grams of phosphine can be obtained from 200.0g of calcium phosphide?

c. How many grams of the other product are formed?

9. Coke will reduce hot arsenious oxide to pure arsenic (As4).

a. Write the balanced equation for this reaction.

b. How much coke would be required to completely reduce 500.0kg of the oxide?

c. How much arsenic is recovered from this reaction?

10. How much iron will be required to release all of the antimony from 10.0g antimony sulfide?

a. Write the balanced equation for this reaction. (Ferrous sulfide is formed).

b. How much antimony is obtained in this reaction?

11. Sodium tetraborate is produced according to the following reaction.

4H3BO3 + 2NaOH ? 7H2O + Na2B4O7

a. How much boric acid is needed to make 150kg of sodium tetraborate?

12. Calcium oxide can be prepared by heating calcium in oxygen.

a. Write the balanced equation for this reaction.

b. How much calcium would be needed to make 15.0g of calcium oxide in this way?

c. If the calcium oxide were prepared by heating calcium carbonate…

i. Write the balanced equation for this reaction.

ii. How much of the carbonate would be required to produce the 15.0g of the oxide?

d. If the calcium oxide were to be obtained by the heating of calcium hydroxide…

i. Write the balanced equation for this reaction.

ii. How much hydroxide would be needed to obtain the 15.0g?

iii. If 15.0g of calcium oxide was allowed to react with the water, what amount of calcium hydroxide would be produced?

13. How much magnesium sulfate is needed to completely react with 145g of sodium chloride?

a. Write the balanced equation for this reaction.

b. How much sodium sulfate could be produced by this reaction?

14. In nature, carbon dioxide in the atmosphere reacts with calcium hydroxide to produce calcium carbonate. This calcium carbonate will react with carbonic acid (carbon dioxide and water) to form calcium bicarbonate.

a. Write both balanced equations for the reactions.

b. What mass of calcium bicarbonate would eventually be produced by the action of carbon dioxide on 1.0g of calcium hydroxide?

15. Hard water, containing calcium bicarbonate as hardness, may be softened by adding sodium hydroxide. Sodium carbonate, calcium carbonate, and water all are formed in the reaction.

a. Write the balanced equation for this reaction.

b. What mass of sodium hydroxide would be needed to react with all the calcium bicarbonate formed in problem 14?

16. Permanent hard water contains calcium sulfate and can be softened by the addition of sodium carbonate.

a. Write the balanced equation for this reaction.

b. What amount of sodium carbonate would have to be added to react with 1.0kg of calcium sulfate?

17. Beryllium hydroxide is amphoteric. It reacts with hydrochloric acid to give beryllium chloride. It also reacts with sodium hydroxide to give sodium beryllate (Na2BeO2).

a. Write both balanced equations for these reactions.

b. If 20.0g of beryllium hydroxide are available, how many grams of beryllium chloride can be prepared?

c. How many grams of sodium beryllate could be made?

d. How many grams of hydrochloric acid would be required for this reaction?

e. How many grams of sodium hydroxide would be required for this reaction?

18. The rare earth element terbium may be prepared by the electrolysis of its fused chloride (valence of terbium= 3).

a. Write the balanced equation for this reaction.

b. How many grams of the chloride would be needed to supply 1.00g of the pure metal?

19. Gadolinium, europium, and samartium may all be prepared in the same way as terbium. All of these elements have a valence of 3.

a. Write the balanced equation for all three equations.

b. How much of the chloride would be required, in each case, to produce 10.0ug of the pure element?

i. Gadolinium

ii. Europium

iii. Samartium

20. The metals: manganese, chromium, indium, and tin are all prepared by the reduction of their oxides with carbon.

a. Write the balanced equation for all 5 reactions (see i-v below).

b. How much carbon will be needed to reduce 100.0kg of each of the following oxides?

i. Manganese dioxide

ii. Chromium (III) oxide

iii. Indium oxide

iv. Tin (II) oxide

v. Tin (IV) oxide

21. Lanthanum and cerium may be obtained in the free state by fusing their respective chlorides with metallic potassium.

a. What amount of the chloride is needed to produce 1.0kg of lanthanum?

b. What amount of the chloride is needed to produce 1.0kg of cerium?

22. Gold will dissolve in the acid mixture known as aqua regia according to the following reaction: Au + HNO3 + 3HCl ? AuCl3 + NO + 2H2O

a. How much aruic chloride will be produced in this reaction when one starts with 5.0mg of gold?

b. How much nitric acid must be added initially to dissolve all this gold?

23. How many kg of coke (carbon) are needed to reduce 100.0kg of lead monoxide to free lead?

24. How much silver bromide can be precipitated by the action of 15.0g of silver nitrate on an excess of sodium bromide?

25. How many grams of sulfuric acid will react exactly with 400.0g of aluminum metal?