lab 5

What were the main results found in this experiment? Include both quantitative results (i.e. important calculated values, including percent error) and qualitative results (i.e. important properties that were investigated).

Imagine you collected a master batch (undiluted) wastewater sample as shown in the illustration below. The total mass of lead (Pb) found in 300 mL of a two-fold diluted master sample was 1.65 µg Calculate the amount of Pb in the master batch sample of the wastewater in ppb. Enter numerical values rounded to one significant figure without units. O Volume of solution: 1 L Mass of solution: 1.1 kg

4. Your lab instructor directs you to use 12.5 grams of the cyclohexanol to start the synthesis. If the density of cyclohexanol is 0.9624 grams/cm³, what volume of cyclohexanol should you measure out in your 25-mL graduated cylinder? Show the calculation completely, giving close attention to the use of units and significant figures.

Solution 1 is diluted by combining 6 mL of Solution 1 with 64 mL of Solution 2. What is the dilution of solution 1?   Report your answer in standard decimal notation rounded to two decimal places. For example, 4 mL added to 16 mL would be a 0.20 dilution. Include trailing zeros if necessary so your answer has two decimal places.

Measurement and Matter Adding or subtracting and multiplying or dividing measurements 1/3 B A chemistry student must write down in her lab notebook the concentration of a solution of sodium hydroxide. The concentration of a solution equals the mass of what's dissolved divided by the total volume of the solution. Here's how the student prepared the solution: The label on the graduated cylinder says: empty weight: 7.2 g . She put some solid sodium hydroxide into the graduated cylinder and weighed it. With the sodium hydroxide added, the cylinder weighed 63.517 g. . She added water to the graduated cylinder and dissolved the sodium hydroxide completely. Then she read the total volume of the solution from the markings on the graduated cylinder. The total volume of the solution was 91.0 mL. What concentration should the student write down in her lab notebook? Be sure your answer has the correct number of significant digits. g-mL G

How many milliliters of 1.50 M potassium hydroxide solution are needed to provide 0.125 moles of potassium hydroxide? Provide an answer correct to 2 significant figures. For example, if you calculate that the correct answer is 12.00 moles, simply type 12 in the box. Do not answer this question using scientific notation. Do not include units in your answer. (hint: this is like the previous problem. You're given two of the three variables in the molarity equation. You need to find the third.)

In a similar experiment, a pair of students was asked to measure out 10.00 mL of water using a 25-mL buret. The data they collected is shown in the table below: Trial Student 1 Student 2 1 9.98 mL 9.97 mL 2 10.00 mL 9.99 mL 3 9.99 mL 10.01 mL Which of the following statements best describes the set of data collected by each student? Student 1 both accurate and precise Student 2 only accurate [ Choose] only accurate both accurate and precise only precise

You collect a sample of seawater containing salt. The original sample weighs 15.67 g. You dry the sample until there is no remaining water. You weigh it again. 0.78 g of salt remains. What was the percent of salt in the sample? Round to the nearest percent.

Use the lab introduction to answer the following question. When answering this problem, report the answer with the appropriate number of significant figures. When entering units, use proper abbreviated units with proper capitalization. A beverage drink mix sample is prepared by mixing a packet of beverage powder in a gallon (3.78 L) of water. A sample for analysis is prepared by diluting 10.00 mL of this solution in a 50.0 mL volumetric flask. When measured using a colorimeter, this diluted solution has an absorbance of (3.4900x10^-1). The calibration curve for the experiment yielded a linear fit of y = (2.240x10^4)x+ (1.22x10^-2) and an R2 value of 0.9911. Determine the molar concentration of food dye in the analyzed sample.

part 1 Which of the following is a best practice in weighing solid samples?   Use weighing paper, a watch glass, a beaker, or some other container to measure mass of your solid samples.   Do not return the mass settings to zero mark; let the next user tare it for you.   Place chemicals directly on the balance pan.   For different trials of an experiment, use multiple balances for your measurements

In Part IV of this lab, the identity of an unknown liquid will be determined by observing some of its physical properties. In lab, a student experimentally obtained the following data recorded below: Solubility in water: soluble Density: 0.785 g/mL Boiling point: 80.9 °C Using Table 1 in the lab manual, determine the identity of the student's unknown liquid. Note: Make sure to read the information box above the table! ethyl alcohol. cyclohexane isopropyl alcohol O There is not enough information to determine the identity.

Part B Gather all of your pennies dated before 1982. Then follow the steps to complete the table. Include units as necessary. Record the number of pennies dated before 1982. Weigh (as a group) the pennies dated before 1982. Record the total mass. If you’re unfamiliar with using an electronic balance, watch this video before continuing. Calculate and record the average mass of a single penny. If you need help with the calculation, visit the averaging data section of the math review. number of pennies: 8 combined mass of the pennies (g): 49.2 average mass of a penny (g): 5.525 Part C Now gather all of your pennies dated after 1982. Complete the table for the post-1982 pennies using the same steps from part B. number of pennies: 9 combined mass of the pennies (g): 51.7 average mass of a penny (g): 5.744 Part D In parts B and C, you measured the average mass of each group of pennies. Now you’ll measure their volume. (For this part, assume that the pennies dated before and after…

Part B Gather all of your pennies dated before 1982. Then follow the steps to complete the table. Include units as necessary. Record the number of pennies dated before 1982. Weigh (as a group) the pennies dated before 1982. Record the total mass. If you’re unfamiliar with using an electronic balance, watch this video before continuing. Calculate and record the average mass of a single penny. If you need help with the calculation, visit the averaging data section of the math review. number of pennies: 8 combined mass of the pennies (g): 49.2 average mass of a penny (g): 5.525 Part C Now gather all of your pennies dated after 1982. Complete the table for the post-1982 pennies using the same steps from part B. number of pennies: 9 combined mass of the pennies (g): 51.7 average mass of a penny (g): 5.744 Part D In parts B and C, you measured the average mass of each group of pennies. Now you’ll measure their volume. (For this part, assume that the pennies dated before and after…

In my on-campus Organic Chemistry II Lab, my students make aspirin. The melting point in the literature for aspirin is 134-136°C.   Suppose the sample of aspirin one of my students made has a melting point range of 129-133 °C.  Using this information, answer the following: 1.  Do you think the student made aspirin?  Why or why not? 2.  How could you test your hypothesis?  Explain what you would do and what the results would look like if they made aspirin versus if they didn't.

Question: How many significant figures are needed for the answers in items 1-3? Please explain why you got that significant figures

6. If the volume of water used in the experiment was 100 mL instead of 50 mL how would the results of the experiment be different? Explain your reasoning.

Can you please answer these and give me an explanation.

Measurement and Matter Adding or subtracting and multiplying or dividing measurements 0/3 B A chemistry student must write down in her lab notebook the concentration of a solution of potassium chloride. The concentration of a solution equals the mass of what's dissolved divided by the total volume of the solution. Here's how the student prepared the solution: The label on the graduated cylinder says: empty weight: 1.500 g She put some solid potassium chloride into the graduated cylinder and weighed it. With the potassium chloride added, the cylinder weighed 40.22 g. She added water to the graduated cylinder and dissolved the potassium chloride completely. Then she read the total volume of the solution from the markings on the graduated cylinder. The total volume of the solution was 172.08 mL. What concentration should the student write down in her lab notebook? Be sure your answer has the correct number of significant digits. A Om g·mL -1 □×1 x10 x 5

If you calculated from your titration that there was 13.75 mg of vitamin C in your fruit juice sample, calculate the concentration of vitamin C in mg/mL. (Concentration = mass/volume) Refer back to the first question on this report (or the procedure) for the volume of your fruit juice sample. Include the unit and two decimal places in your answer.   First question answer 20.00 mL

2

Sucrose solution for experiment 1: (Question a-c)Prepare a solution of sucrose by accurately weighing 9.0 – 9.25 g of sucrose into a 100mLbeaker / conical flask. Record the mass of the sample. Add 25 mL distilled water. Mix until allcrystals dissolve.NaCl solution for experiment 2: (Question d-f)Prepare a solution of NaCl by accurately weighing approximately 1.5 g of NaCl into a 100 mLbeaker / conical flask. Record the mass of the sample. Add 25 mL distilled water. Mix until allcrystals dissolve.MgCl2٠6H2O solution for experiment 2: (Question d-f)Prepare a solution of magnesium chloride by accurately weighing approximately 3.6 g ofMgCl2٠6H20 into a 100 mL beaker / conical flask. Record the mass of the sample. Add 25 mLdistilled water. Mix until all the crystals dissolve

you combined 25 ml of milk with 30 ml of vinegar. After 10 minutes you observe the mixture again and the graduated cylinder now reads a total of 51.5 ml. How many ml have evaporated from the mixture?

Jacquel Adding or subtracting and multiplying or dividing measurements A chemistry student must write down in her lab notebook the concentration of a solution of potassium chloride. The concentration of a solution equals the mass of what's dissolved divided by the total volume of the solution. Here's how the student prepared the solution: • The label on the graduated cylinder says: empty weight: 4.200 g • She put some solid potassium chloride into the graduated cylinder and weighed it. With the potassium chloride added, the cylinder weighed 71.0 g. • She added water to the graduated cylinder and dissolved the potassium chloride completely. Then she read the total volume of the solution from the markings on the graduated cylinder. The total volume of the solution was 133.0 mL. What concentration should the student write down in her lab notebook? Be sure your answer has the correct number of significant digits. Ch 8 mL Explanation Check O2021 McGraw-Hill Education All Rights Reserved…

A student measured 10.5 mL of a stock caffeine solution with a concentration of 52.3 mg/mL and diluted it to 29.5 mL. Calculate the final concentration of the diluted caffeine solution. NOTE! Do not include any units in your answer. Answer with incorrect # of significant figures will be marked incorrect. Type your answer...

A hard water solution contains 4.4 grams of calcium chloride.

All boxes please. Answer choices: analytical technique or purpose

O MEASUREMENT Adding or subtracting and multiplying or dividing measurements A chemistry student must write down in her lab notebook the concentration of a solution of sodium hydroxide. The concentration of a solution equals the mass of what's dissolved divided by the total volume of the solution. Here's how the student prepared the solution: • The label on the graduated cylinder says: empty weight: 1.5 g • She put some solid sodium hydroxide into the graduated cylinder and weighed it. With the sodium hydroxide added, the cylinder weighed 36.669 g. • She added water to the graduated cylinder and dissolved the sodium hydroxide completely. Then she read the total volume of the solution from the markings on the graduated cylinder. The total volume of the solution was 37.11 mL. What concentration should the student write down in her lab notebook? Be sure your answer has the correct number of significant digits. g mL Explanation -1 Check 99+ 0/5 VUDU © 2023 McGraw Hill LLC. All Rights…

Suppose your instructor places a can of regular and diet cola in a large container filled with water. What might you expect happen based on the results of this experiment?

1. All answers to be entered via short answer are in the numerical format and presented up to the 3rd decimal place. Add trailing zeros if necessary, to complete your answer. NO NEED TO INCLUDE THE UNIT. For uniformity of answers, please be guided by the following examples: If your answer is 5.627594, enter 5.628 If your answer is 3.129934, enter 3.130 If your answer is 8.38, enter 8.380 If your answer is 1.2, enter 1.200 If your answer is 25, enter 25.000 If your answer is less than the value of 1, always place a zero before the decimal point (example: 0.5, enter 0.500) 2. In cases for answers in the exponential format, please be guided by the following examples and format: Do not convert your answer to decimal format If your answer from the calculator is 1.23454566 x 10E-4, enter 1.235x10^-4 (no spaces in between) If your answer from the calculator is 7.379566 x 10E-5, enter 7.38x10^-5 (no spaces in between) 3. For the atomic weights, it should be rounded to the nearest whole…

1. All answers to be entered via short answer are in the numerical format and presented up to the 3rd decimal place. Add trailing zeros if necessary, to complete your answer. NO NEED TO INCLUDE THE UNIT. For uniformity of answers, please be guided by the following examples: If your answer is 5.627594, enter 5.628 If your answer is 3.129934, enter 3.130 If your answer is 8.38, enter 8.380 If your answer is 1.2, enter 1.200 If your answer is 25, enter 25.000 If your answer is less than the value of 1, always place a zero before the decimal point (example: 0.5, enter 0.500) 2. In cases for answers in the exponential format, please be guided by the following examples and format: Do not convert your answer to decimal format If your answer from the calculator is 1.23454566 x 10E-4, enter 1.235x10^-4 (no spaces in between) If your answer from the calculator is 7.379566 x 10E-5, enter 7.38x10^-5 (no spaces in between) 3. For the atomic weights, it should be rounded to the nearest whole…

1. All answers to be entered via short answer are in the numerical format and presented up to the 3rd decimal place. Add trailing zeros if necessary, to complete your answer. NO NEED TO INCLUDE THE UNIT. For uniformity of answers, please be guided by the following examples: If your answer is 5.627594, enter 5.628 If your answer is 3.129934, enter 3.130 If your answer is 8.38, enter 8.380 If your answer is 1.2, enter 1.200 If your answer is 25, enter 25.000 If your answer is less than the value of 1, always place a zero before the decimal point (example: 0.5, enter 0.500) 2. In cases for answers in the exponential format, please be guided by the following examples and format: Do not convert your answer to decimal format If your answer from the calculator is 1.23454566 x 10E-4, enter 1.235x10^-4 (no spaces in between) If your answer from the calculator is 7.379566 x 10E-5, enter 7.38x10^-5 (no spaces in between) 3. For the atomic weights, it should be rounded to the nearest whole…

1. All answers to be entered via short answer are in the numerical format and presented up to the 3rd decimal place. Add trailing zeros if necessary, to complete your answer. NO NEED TO INCLUDE THE UNIT. For uniformity of answers, please be guided by the following examples: If your answer is 5.627594, enter 5.628 If your answer is 3.129934, enter 3.130 If your answer is 8.38, enter 8.380 If your answer is 1.2, enter 1.200 If your answer is 25, enter 25.000 If your answer is less than the value of 1, always place a zero before the decimal point (example: 0.5, enter 0.500) 2. In cases for answers in the exponential format, please be guided by the following examples and format: Do not convert your answer to decimal format If your answer from the calculator is 1.23454566 x 10E-4, enter 1.235x10^-4 (no spaces in between) If your answer from the calculator is 7.379566 x 10E-5, enter 7.38x10^-5 (no spaces in between) 3. For the atomic weights, it should be rounded to the nearest whole…

You have been hired as a lab assistant! your first task is to make 5.0 L of a solution that is 35.8% NaCl (salt) by weight water. How much salt should you add to the 5.0 L of water to prepare this solution? Report the mass of salt in kilograms

How many mL of (5.0300x10^0) M NANO3 would be needed in a dilution experiment to make (8.56x10^2) mL of (2.3400x10^0) M NANO3? Enter your answer in scientific notation with 3 sig figs. Do not include any units in your answer. Do not round any intermediate calculations. Note: Your answer is assumed to be reduced to the highest power possible. Your Answer: x10 Answer