17) In an experiment the value for beta has been shown to be .7503, what is the power of this experiment? 

18) A researcher did a one-tailed hypothesis test using an alpha level of .01, H0 was rejected. A colleague analyzed the same data but used a two-tailed test with α=.05, H0 was failed to reject. Can both analyses be correct? Explain your answer.

21) A psychologist would like to examine the effect of fatigue on mental alertness. An attention test is prepared which requires subjects to sit in front of a blank TV screen and press a response button each time a dot appears on the screen. A total of 110 dots are presented during a 90-minute period, and the psychologist records the number of errors for each subject. Two groups of subjects are selected. The first group (n=5) is tested after they have been kept awake for 24 hours. The second group (n=10) is tested in the morning after a full night’s sleep. The data for these two samples are as follows:

____________________________________

Awake 24 hours     Rested

____________________________________

x̅=35     x̅=24

ss=120 ss=360

____________________________________

On the basis of these data, can psychologist conclude that fatigue significantly increases errors on an attention task? Test with α=.05 and report effect size. 

There is only an Experiment 1 in this lab.

Experiment 1: Double Replacement Precipitation Reaction between Calcium Chloride and Sodium Carbonate

In this experiment you will precipitate calcium carbonate from the reaction between sodium carbonate and calcium chloride. The reaction is:

Procedure

Place a weigh boat on the scale. Once you have the mass of your weigh boat, press the button on the right hand side (0/T). Your scale should now read 0.0 g.Use your metal spatula to weigh out 2.0 g of CaCl2 in the weigh boat (the total mass should be 2.0 g). Record the exact mass of the powder in Table 9.Be sure to wipe off your spatula, gloves, and scale on a paper towel between chemical samples to avoid cross-contamination.Add the 2.0 g of CaCl2 to the 250 mL beaker. Use the 100 mL graduated cylinder to add 50 mL of distilled water to the beaker and mix with the glass stir rod until all CaCl2 has dissolved.

Note: This is an exothermic process, so the beaker may become warm.

Place a 50 mL beaker on the scale. Once you have the mass of your beaker, press the button on the right hand side (0/T). Your scale should now read 0.0 g.Use your metal spatula to weigh out 2.5 g of Na2CO3 in the 50 mL beaker. Record the exact mass of the powder in Table 9.Remove the beaker from the scale. Use your 100 mL graduated cylinder to add 25 mL of distilled water to the 50 mL beaker and mix with the glass stir rod until all Na2CO3 has dissolved. Add all of the Na2CO3 solution to the beaker containing the CaCl2 solution. It is important that all of the Na2CO3 is added. To ensure this, rinse the 50 mL beaker with up to 5 mL distilled water, and pour the rinse into the CaCl2 solution.Stir the solution for three minutes. Then, allow it to sit for 15 minutes. This gives sufficient time for all CaCO3 to precipitate. Record your observations in Table 9.While the solution is sitting, set up the gravity filtration apparatus (Figure 4). Place a funnel in the 250 mL Erlenmeyer flask, such that the bottom of the funnel is also inside the mouth of the flask. Obtain a piece of filter paper. Use the scale to weigh the filter paper and record the mass in Table 9.Prepare a filtering funnel as shown in Figure 5. Fold a piece of filter paper in half twice to make quarters, and place the paper in the funnel so that three quarters are open on one side and one quarter is on the opposite side. Place the paper into the funnel and seat with a small amount of distilled water (this will prevent the filter paper from rising up).  Slowly filter the solution from the beaker. Additional distilled water may also be used to transfer any remaining solid into the filtration apparatus. After all the solution has been filtered, use the pipette to rinse the filter paper with approximately 5 mL of isopropyl alcohol to aid the drying process. Allow the isopropyl alcohol to completely drip through the filter before removing filter paper from the funnel. Carefully remove the filter paper from the funnel and put it precipitate-side up in a safe place to dry overnight. Air drying will take anywhere from 5 to 18 hours, depending on the humidity of your region. Allow the product to dry, undisturbed, and determine the mass of the product recovered (Experimental Yield) by re-weighing the system and subtracting the weight of the filter paper. Record the data in Table 9.

Lab questions

1. Which is the limiting reagent, CaCl2 or Na2CO3? What is the theoretical yield of the product CaCO3? Show all work to prove your answers. Use the correctly balanced equation given in the Procedure

2. What happens to the excess reactant after the reaction is complete?

3. Use the following equation to find the percent yield of CaCO3. Show all work. The Experimental Yield is found in Table 9 and the Theoretical Yield is from question 1 above.

4. Explain why an experimental yield from an experiment (not necessarily this one) could be LOWER than the theoretical yield (i.e. the percent yield is less than 100%). HUMAN ERROR and CALCULATION ERROR are unacceptable reasons. It is expected that you follow all procedures to the letter, and that you know how to do the calculations properly (or find appropriate help to get the calculations right).

5. Explain why an experimental yield from an experiment (not necessarily this one) could be HIGHER than the theoretical yield (i.e. the percent yield is more than 100%). HUMAN ERROR and CALCULATION ERROR are unacceptable reasons. It is expected that you follow all procedures to the letter, and that you know how to do the calculations properly (or find appropriate help to get the calculations right).
6. What is the theoretical yield of CaCO3 if 6.0 g of CaCl2 (instead of 2.0 g) is used for the reaction while the amount of Na2CO3 remains the same at 2.5 g? Support your answer with calculations and numerical values. Show all work. Again, re-read the Introduction the lab Moodle shell and the example before the Post Lab Questions.

Experiment : Determination of Water Hardness Using a Titrator

EDTA 0.010 M used for the experiment

the titrator with 7–9 mL of distilled water. = I used 9mL

the graduated cylinder to measure exactly 10 mL of tap water from your faucet.

Add 5 drops of pH 10 buffer solution to the 10 mL of tap water in the beaker

Dip approximately 10 mm of a toothpick into the distilled water. Then, while toothpick is still damp, dip the toothpick into the EBT indicator powder.

Dip the EBT-covered toothpick end into the water in the beaker and carefully stir, to transfer all of the EBT from the toothpick into the water.

Carefully swirl the beaker for 30–60 seconds to fully dissolve the EBT into the water solution. The EBT indicator will cause the water solution to turn a pale purple-pink color.

Open the stopcock and add 1 drop of (EDTA 0.010 M) to the purple-pink water sample in the beaker. After the drop is added, gently swirl the beaker and observe the color for 5 seconds.

And repeat this trial 3 times of titration  

• Using the following equation, determine the average concentration (moles per liter) of Ca2+ ions present in your water. Record the concentration in Data Table 2.

mol Ca2+L =L EDTA × mol EDTAL × 1 mol Ca2+1 mol EDTA × 10.010 L water

Note: PPM is equivalent to mg/L for dilute solutions.

ppm CaCO3 = mol Ca2+1L×1 mol CaCO31 mol Ca2+×100.06 g CaCO31 mol CaCO3×1000 mg1g

Please help what should I be getting for these questions based on my results. explain also is 28 ppm Correct? For the first table

QUESTIONS

1. Based on the analysis of your local water, would you classify its hardness as soft, moderate, hard, or very hard? Explain your answer.

2. Approximately how much calcium would you ingest by drinking eight 8-oz glasses of your local water? Hint: 1 oz (fluid ounce) = 29.57 mL.

3. Assume an average minimum daily requirement for calcium is 1,150 mg. Calculate what percentage of your daily requirements could be met by drinking 1.0 L of your local water.

Experiment 1: Exploring Charge with Scotch® Tape
In this experiment, you will observe the behavior of charged objects using pieces of Scotch® tape.

Materials
Scotch® Tape
Ruler
*Pen     
*Flat Work Surface

  

Procedure
Part 1
1.   Use the ruler to measure a piece of tape that is 10 cm long.
2.   Tear the tape to remove the 10 cm piece from the roll.
3.   Create a “handle” on one side of the piece of tape by folding down the piece of tape 1 cm from the end, leaving a 9 cm sticky piece with a 1 cm handle.
4.   Stick the entire sticky surface of the tape to a table top, counter top, or another flat surface.
5.   Repeat Steps 1 – 4 with a second 10 cm piece of tape. Stick the second piece of tape at least 15 cm away from the first piece on the same surface.
6.   Quickly pull off both strips of tape from the surface and ensure that the pieces do not touch.
7.   Carefully bring the non-sticky sides of the tape together and record observations about the behavior of the pieces in Table 1.
8.   Discard the tape.
Part 2
1.   Use the ruler to measure a piece of tape that is 10 cm long.
2.   Tear the tape to remove the 10 cm piece from the roll.
3.   Create a “handle” on one side of the piece of tape by folding down 1 cm of tape from one end.
4.   Stick the entire sticky surface of the tape to a table top, counter top, or another flat surface.
5.   Use a pen and write “B1” on the tape. “B” stands for bottom.
6.   Repeat Steps 1 – 4 with a second 10 cm piece of tape. This time, press the second strip of tape on top of the one labeled “B1”.
7.   Use the pen to label the top piece with a “T1”. “T” stands for top.
8.   Create a second pair of pieces of tape by repeating Steps 1 – 7. This time, label the bottom piece “B2” and the top piece “T2”.
9.   Use the T1 handle to quickly pull off T1 strip of tape from the flat surface.
10.   Use the B1 handle to peel off the bottom strip from the flat surface. Keep both B1 and T1 pieces away from each other.
11.   Bring the non-sticky sides of B1 and T1 together and record observations about the behavior of the pieces in Table 1.
12.   Set the pieces of tape, non-sticky side down, on the table approximately 15 cm away from each other. Do not stick them back on the table!
13.   Repeat Steps 9 - 12 for B2 and T2.
14.   Carefully bring the non-sticky sides of piece “T1” and “B2”. Record observations about the behavior of the pieces in Table 1.
15.   Set them back down, non-sticky side down.
16.   Repeat Steps 14 - 15 for “T1” and “T2”. Record your observations in Table 1.
17.   Repeat Steps 14 - 15 for “B1” and “B2”. Record your observations in Table 1.
18.   Repeat Steps 14 and 15 for “T1” and the hair on your leg or arm. Record your observations in Table 1.
19.   Repeat Steps 14 and 15 for “B1” and the hair on your leg or arm. Record your observations in Table 1.

Table 1: Electric Charge Observations

***The observation is filled.

Post-Lab Questions

1.   Describe the interaction between the top and bottom strips as they relate to electric charge. Did the behavior of the pieces change when the tape was from different sets?

2.   Describe the interaction between two top and two bottom pieces of tape as they relate to electric charge. Is this consistent with the existence of only two types of charge? Use your results to support your answer.

3.   Did the top tape attract your arm hair? Did the bottom tape attract your arm hair? Usually arm hair is neutral; it has equal number positive and negative charges. Use this information to explain your results.

4.   Which pieces of tape are positively charged? Which pieces of tape are negatively charged? Explain your reasoning.

5.   Use your data to create a rule describing how like charges, opposite charges, and neutral bodies interact.

6.   What do you observe about the force of attraction or repulsion when the pieces of tape are closer together and farther apart? Does this change happen gradually or quickly?

1. In this distillation experiment we start the experiment with 10 mL of liquid mixture ofcyclohexane and toluene. However, it is not possible to obtain all 10 mL back under thecurrent procedure particularly for fractional distillation. Explain why that is the case for distillation and in particular for fractional distillation.

2. How could you modify the experiment and collect all 10 mL of the startingmaterials.

3. Plot a theoretical distillation curve of temperature (y-axis) vs. volume in mL (x-axis) fora 15 mL of a mixture containing 60% 1-propanol and 40% 2-propanol. Are these twocompounds easier to separate by distillation than cyclohexane and toluene? Explain youranswer.

4. In this experiment you were asked to collect two fractions and early fraction and a latefraction. Which of the two fractions would be richer in cyclohexane? Would there be adifference between the percent of cyclohexane in the fractions collected from fractionalvs. simple distillation.

5. What method of purification would you use to purify methanol from a solution ofmethanol and NaCl? Be specific and explain your choice of method.

Experiment - Claisen Condensation Reactions:

In this experiment, we performed a Claisen condensation reaction of ethyl phenylacetate using potassium tert-butoxide to form ethyl 3-oxo-2,4-diphenylbutanoate and ethanol without using a solvent. This allowed us to reduce waste, have reagents that have a relatively low toxicity level, and made the reaction much more convenient.

Question 2: If this reaction were run in a solution (as opposed to solvent-free) it would require several hours of refluxing and provide a much smaller yield. Why is this the case?

I cannot seem to find an answer to this question. The only thing that I can find is that the reaction is reversible when a solvent is used (which I'm assuming means that the reaction is not reversible when there is no solvent). If this is correct, why is the reaction reversible when a solvent is used, and not reversible when a solvent is not used?

A source for the answer would be appreciated if possible.

Thank you for the help in advance!

Company A began operations on January 1, 2016. At the end of 2016, the company recorded bad debt expense of $1,500. On July 1, 2017, Company A wrote off as uncollectible $800 of accounts receivable. On August 31, 2017, the company reversed $200 of the write-offs made on July 1st. On December 31, 2017, the company estimated that 3% of its total accounts receivable would be uncollectible. Accounts receivable were $150,000 on December 31, 2017. The journal entry on July 1, 2017 includes a debit to ( ) for ( ) and a credit to ( ) for ( ).

Below is a Proper Data Set of classes that Business students have taken at Highline. Each line or record in the Table represents a class that a student took at Highline. There are 227 Rows (Records) in the Table. The Quarter Column represents the quarter the class was taken The Year Column represents the quarter the class was taken The Department Column represents the quarter the class was taken The Class # Column represents the quarter the class was taken The Credits Column represents the quarter the class was taken The Grade Column represents the quarter the class was taken Using a PivotTable, create a Joint Probability Table for the variables (Column) Department and Quarter).

1. Let V be real vector space (possibly infinite-dimensional), S, T ∈ L(V ), and S be in- vertible. Prove λ ∈ C is an eigenvalue of T if and only if λ is an eigenvalue of STS−1. Give a description of the set of eigenvectors of STS−1 associated to an eigenvalue λ in terms of the eigenvectors of T associated to λ.

2. Show that there exist square matrices A, B that have the same eigenvalues, but aren’t similar. Hint: Use the identity matrix as one of the matrices.