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What is the volume of a 7.75 g sample of carbon monoxide gas at a temperature of -19.7 oC and a pressure of 764.7 mmHg?
What is the pressure exerted by 2.48 g of nitrogen with a volume of 2925.6 mL at a temperature of 22.3oC?
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Ashford University Environmental Science Hetchy Case Study
Hetch Hetchy Case StudyInstructions1. What were some of your first thoughts about the Hetch Hetchy Valley prior to the beg ...
Ashford University Environmental Science Hetchy Case Study
Hetch Hetchy Case StudyInstructions1. What were some of your first thoughts about the Hetch Hetchy Valley prior to the beginning of the dam construction? Would it be a place you would have liked to visit and spend time exploring or would you not be interested in something like that? Why or why not?2. The earthquake and following fires of San Francisco of 1906 were the events that justified the beginning of the Hetch Hetchy Project. The actual project didn't start until 1914 and water wasn't delivered to the Bay Area for the first time until 1934. Based on this timeline information from the case study, how justifiable was the project for the purpose of helping out San Francisco after the earthquake? Do you think other factors were involved in this process? Why and what could those have been? Describe at least 2 factors.3. The Hetch Hetchy environmental drama has been an issue now for a century. The same reasons it was originally debated are essentially the same reasons it is still debated today. Where do you stand on this environmental argument? Are you for the restoration of the Hetch Hetchy Valley by demolition to some extent of the O'Shaughnessy Dam or are you opposed to the restoration of the Hetch Hetchy Valley? Provide at least three reasons to demonstrate your support or opposition to the restoration of the valley.4. Regardless of if you are in favor of the restoration of the valley or not, if it were restored then it could become part of Yosemite National Park. A common complaint guests have after visiting Yosemite is that it is too crowded with other tourists. Some suggestions for controlling the number of visitors to Yosemite each year is to raise the price of entering the park so not everyone can afford admittance, have a lottery each year to determine who can enter the national park, or have park officials limit the number of guests entering the gate each day. Do these options seem reasonable to you? Why or why not? If Hetch Hetchy was restored and became part of Yosemite, many have wondered if more people would visit there and help reduce the flow of visitors to the more crowded parts of Yosemite. Currently, Hetch Hetchy is not an area that is visited by tourists on a regular basis like Yosemite. Do you think that might help with the congestion of visitors at Yosemite? Why or why not?
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MOS 5201 CSU Introduction to Safety Engineering Discussion
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MOS 5201 CSU Introduction to Safety Engineering Discussion
THESE (4) QUESTION Explored Hierarchy of Controls in the areas of walking and working surfaces, tools and machines, and materials handling. Please further explore the hazards and their controls in the areas of pressure, ionizing radiation, and ventilation please see question attached.QUESTION 1Your quality control/quality assurance manager has requested your assistance in the testing and repair facility. One of the test procedures utilizes a radiation source that is emitting gamma radiation at a rate of 50 mrem/hour at a distance of 1 foot. This testing is done for approximately 2 hours per day, 2 days per week. The Occupational Safety and Health Administration (OSHA) has a PEL of 1.25 rem per quarter and 5 rem per year.Determine the employee's exposure for 1 year.Calculate the exposure rate if the employee was moved to a distance of 3 feet from the radiation source.Calculate the exposure rate of the employee if a 5 cm lead shield was installed between the source and the detector. The employee is working at a distance of 1 foot from the source. [µ for lead, (662 keV gamma ray) = 1.23cm-1]Your response must be at least 200 words in length.QUESTION 2There are several gas cylinders that are under pressure, which are located outside of the maintenance department. As the safety professional, you have been asked a couple of questions regarding this issue. Please provide the correct responses and discuss your recommendations for any control measures.The volume of the gas cylinder is 25.7 liters and exerts a pressure of 670 mmHg. If part of the gas is used, the pressure drops to 595 mmHg. What would be the remaining volume of gas?One of the cylinder's content is under pressure at 1900 psi (per the gauge) at 70°F. As the day heats up because of the sun, the temperature increases to 105°F. What is the pressure at 105°F?Your response must be at least 200 words in length.QUESTION 3The maintenance manager of your facility has asked you to evaluate a particular welding booth that utilizes a local exhaust ventilation (LEV) system to remove the contaminant at the source. The exhaust system does not appear to be drawing enough of the welding fumes away from the employees to reduce the iron oxide below the permissible exposure limit (PEL) of 10 mg/m3. During your investigation, you determine that the diameter of the duct system is 8 inches and has an air velocity of 350 fpm (feet per minute). The welding operation is performed at a distance of 1.5 feet from the exhaust opening. Determine the flow rate, and provide your recommendations on the control measures that could improve the capture of the iron oxide contaminant.Your response must be at least 200 words in length.QUESTION 4A process involves the removal of oil and other liquid contaminants from metal parts using a heat-treat oven, which has a volume of 15,000 ft3. The oven is free of solvent vapors. The ventilation rate of the oven is 2,100 cfm, and the safety factor (K) is 3. The solvent used in the process evaporates at a rate of 0.6 cfm (cubic feet per minute). The operator would like to know how long it would take the concentration to reach 425 ppm.Your response must be at least 200 words in length.
BIOL 1011 Measuring the Rate of Photosynthesis Lab Report
*Lab is not needed to complete this assignment* You are simply making notes based on facts as in what will happen in the s ...
BIOL 1011 Measuring the Rate of Photosynthesis Lab Report
*Lab is not needed to complete this assignment* You are simply making notes based on facts as in what will happen in the situations. Answer all questions and make notes for all statements. Please also fill in the attached document!PhotosynthesisBackgroundFigure 1. The mouse, Mus musculusCan a Mouse Survive in a Jar?Oxygen was discovered over 200 years ago when Joseph Priestley experimented with mice in jars. He closed a mouse in an airtight jar and, after a short time, the mouse collapsed. Priestley then closed a plant in an airtight jar and it survived for weeks. So he decided to combine the two. The mouse in the jar with the plant was able to survive long past the mouse alone in the jar.Photosynthesis was not explained during Priestley's lifetime, so he never found out that the plant in the jar generated oxygen through photosynthesis and that is why the mouse was able to survive. Comparatively, the mouse that collapsed had used up all the oxygen in the jar.PhotosynthesisHumans, like other animals, require food to generate energy. Plants, in contrast, produce their own food. They use the process of photosynthesis to use carbon dioxide (CO2) and sunlight from the environment in order to generate molecules of sugar. Sugar is further converted to chemical energy that plants need to sustain their existence.Photosynthesis has been used by organisms for millions of years. The first photosynthetic organisms were the ancestors of modern-day cyanobacteria. Photosynthesis takes sunshine, CO2 from the air, and some hydrogen atoms from water to produce two very important molecules — glucose (C6H12O6) and oxygen (O2).The basic formula for photosynthesis is:6CO2+6H2O⟶C6H12O6+6O2carbon dioxide + water ⟶ glucose + oxygenPhotosynthetic organisms are the foundation of every ecosystem because they take limited inputs and produce physical matter. In this role, they are referred to as producers. Organisms that consume producers are accordingly called consumers.Photosynthesis takes place inside chloroplasts, special organelles located in the cells of plants and other photosynthesizing organisms. Chloroplasts are green because they utilize the pigment chlorophyll. The primary light-absorbing organs of plants are the leaves. Although chloroplasts are located in cells throughout a plant, chloroplast density is by far the highest in the leaves. Between 440,000 and 790,000 chloroplasts can be found per square millimeter in the leaf of a plant.One of the byproducts of photosynthesis is oxygen, an essential molecule vital to the existence of humans and animals on Earth. Earth’s atmosphere is about 22% oxygen and most of the remainder is nitrogen. Humans and animals rely on plants as the source of their oxygen.Rate of PhotosynthesisThe rate of photosynthesis is affected by a number of factors:Light intensityTemperatureAvailability of waterAvailability of nutrientsThere is a maximum rate of photosynthesis that is constrained by the limits of these factors. For example, there is a value for light intensity above which the rate of photosynthesis can no longer increase. Similarly, increasing the temperature from 10 °C to 20 °C will increase the rate of photosynthesis, because enzymes in the plant will be closer to their optimal working temperatures, and molecules in the cells will move faster owing to increased kinetic energy. However, if the temperature is raised above a certain level, the rate of photosynthesis will drop as plant enzymes are denatured.Net Exchange of GasesIt is important to remember that while carrying out photosynthesis in the chloroplasts, the plant is also carrying out cellular respiration, which releases CO2. In this lab, you will measure the net rate of gas exchange for the combined processes of photosynthesis and cellular respiration.The CO2 for photosynthesis is supplied in this experiment by sodium bicarbonate dissolved in water. CO2 is much more soluble in water than oxygen is. More CO2 is used up by photosynthesis than is released by respiration. Therefore, it is expected that the net change in CO2 will be negative. This means that more CO2 will go into the plant than will be removed from the water.On the other hand, oxygen is not very soluble in water, but is produced during photosynthesis. Therefore, it is expected that its net change will be positive. This means that the plant produces more oxygen during photosynthesis than it consumes in respiration.Overall, the gas being produced and measured is oxygen.A plant’s rate of respiration can be determined by measuring the rate of oxygen uptake during periods of darkness, when no photosynthesis takes place. Again, oxygen's insolubility in water helps with this measurement. As the plant respires, oxygen is removed from the gas in the system. At the same time, CO2 is released but remains dissolved in the water. The total change in the volume of the solution is negligible.About This LabIn this lab, you will measure the rate of photosynthesis in the aquatic plant Elodea under various conditions. You will measure the rate of photosynthesis by observing gas production. You will explore the gas exchange of the plant with its environment in both light and dark conditions and observe if photosynthesis and respiration take place in parallel when light is present.You will modify the light source intensity to test how the rate of photosynthesis changes depending on the intensity of light falling on the leaves of the plant. You will also test the effect of temperature on the rate of photosynthesis.ExperimentsOpen the simulation by clicking on the virtual lab icon below. The simulation will launch in a new window.You may need to move or resize the window in order to view both the Procedure and the simulation at the same time.Follow the instructions in the Procedure to complete each part of the simulation. When instructed to record your observations, record data, or complete calculations, record them for your own records in order to use them later to complete the post-lab assignment.ProceduresExperiment 1: Measuring the Rate of PhotosynthesisPart 1: Set-upTake a plant light box from the Instruments shelf and place it on the workbench.Take a 250 mL Erlenmeyer flask from the Containers shelf and place it onto the workbench.Take a branch of Elodea from the Materials shelf and add it to the Erlenmeyer flask.Add 100 mL of 0.1 M sodium bicarbonate solution from the Materials shelf to the Erlenmeyer flask. Make sure the solution covers the branch, as Elodea is a submergent aquatic plant and acquires carbon dioxide from the water. Record the plant name and the solution the plant is in to reference later.Place the Erlenmeyer flask into the plant light box. Set the temperature of the plant light box to 20 °C, which is around room temperature. Record the temperature to reference later.Switch the plant light intensity of the plant light box to 5, the maximum. This setting is located next to the gray Start button in the upper right corner of the plant light box. Record the plant light intensity to reference later.Set the timer to 120 minutes.Part 2: Collecting Oxygen Produced by the PlantThe rate of photosynthesis can be measured by collecting the oxygen produced by the plant.Take a gas syringe from the Instruments shelf and place it onto the plant light box. Record the initial volume in mL of gas in the syringe at 0 min of the experiment (countdown timer reads 120 min) to reference later. To see the volume, double-click on the gas syringe. Press the gray Start button in the upper right corner of the plant light box. After 30 simulated minutes in the plant light box (countdown timer will read 90 min), press the lab pause button in the lower left corner of the lab (Figure 1) to note the gas volume in the syringe.Figure 1. Lab Pause ButtonAfter recording the simulated time and gas volume to reference later, press the lab play button (Figure 2) to resume the experiment.Figure 2. Lab Play ButtonRepeat this pausing and playing sequence to note and record the gas volume in the syringe after:60 simulated minutes (countdown timer reads 60 min)90 simulated minutes (countdown timer reads 30 min)120 simulated minutes (countdown timer reads 0 min)When the door of the plant light box opens to indicate this run is done, make sure to leave everything in place for the next experiment. Experiment 2: Respiration in the DarkChange the light intensity of the plant light box all the way down to 0 for dark conditions. Record the plant light intensity and temperature settings to reference later.Set the timer to 120 minutes. Record the initial volume at 0 min of the experiment (countdown timer reads 120 min) of gas in the syringe to reference later.Press the gray Start button.Using the lab pause and play buttons as needed, record the syringe's gas volume after:30 simulated minutes (countdown timer reads 90 min)60 simulated minutes (countdown timer reads 60 min)90 simulated minutes (countdown timer reads 30 min)120 simulated minutes (countdown timer reads 0 min)When the door of the plant light box opens, move the flask to the waste to empty it.Place the empty flask in the sink.Double-click the gas syringe and reset the plunger. Make sure the volume goes back to 0.00 mL.Experiment 3: Effect of Light IntensityRepeat the set-up outlined in Experiment 1, Part 1, steps 2 – 9. However, this time set the plant light intensity to 4. Record the initial volume of gas in the syringe at 0 min of the experiment (countdown timer reads 120 min) to reference later.Press the gray Start button, then use the lab pause and play buttons to note and record the syringe's gas volume after:30 simulated minutes (countdown timer reads 90 min)60 simulated minutes (countdown timer reads 60 min)90 simulated minutes (countdown timer reads 30 min)120 simulated minutes (countdown timer reads 0 min)Record the plant light intensity and temperature settings to reference later.When the door of the plant light box opens, move the flask to the waste to empty it.Place the empty flask in the sink.Double-click the gas syringe and reset the plunger. Make sure the volume goes back to 0.00 mL.Repeat the procedure outlined in steps 1 – 7 for the following plant light intensity settings:321Experiment 4: Effect of Environmental TemperatureSet the plant light intensity of the plant light box to 5 and the timer to 60 minutes. Record the light intensity setting to reference later.Take a 250 mL Erlenmeyer flask from the Containers shelf and place it onto the workbench.Take a branch of Elodea from the Materials shelf and add it to the flask.Add 100 mL of 0.1 M sodium bicarbonate from the Materials shelf to the flask.Place the flask into the plant light box.Set the temperature of the plant light box to 10 °C. Record the temperature setting to reference later.Record the initial volume of gas in the syringe at 0 min of the experiment (countdown timer reads 60 min) to reference later.Press the gray Start button.Record the volume in the gas syringe after 60 simulated min (countdown timer reads 0 min) to reference later.Move the flask to the waste to empty it.Place the empty flask in the sink.Double-click the gas syringe and reset the plunger. Make sure the volume goes back to 0.00 mL.Repeat steps 2 – 12 for two additional temperatures:30 °C40 °CClear the bench of all materials, containers, and instruments, then return to your course page to complete any assignment for this lab.
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Ashford University Environmental Science Hetchy Case Study
Hetch Hetchy Case StudyInstructions1. What were some of your first thoughts about the Hetch Hetchy Valley prior to the beg ...
Ashford University Environmental Science Hetchy Case Study
Hetch Hetchy Case StudyInstructions1. What were some of your first thoughts about the Hetch Hetchy Valley prior to the beginning of the dam construction? Would it be a place you would have liked to visit and spend time exploring or would you not be interested in something like that? Why or why not?2. The earthquake and following fires of San Francisco of 1906 were the events that justified the beginning of the Hetch Hetchy Project. The actual project didn't start until 1914 and water wasn't delivered to the Bay Area for the first time until 1934. Based on this timeline information from the case study, how justifiable was the project for the purpose of helping out San Francisco after the earthquake? Do you think other factors were involved in this process? Why and what could those have been? Describe at least 2 factors.3. The Hetch Hetchy environmental drama has been an issue now for a century. The same reasons it was originally debated are essentially the same reasons it is still debated today. Where do you stand on this environmental argument? Are you for the restoration of the Hetch Hetchy Valley by demolition to some extent of the O'Shaughnessy Dam or are you opposed to the restoration of the Hetch Hetchy Valley? Provide at least three reasons to demonstrate your support or opposition to the restoration of the valley.4. Regardless of if you are in favor of the restoration of the valley or not, if it were restored then it could become part of Yosemite National Park. A common complaint guests have after visiting Yosemite is that it is too crowded with other tourists. Some suggestions for controlling the number of visitors to Yosemite each year is to raise the price of entering the park so not everyone can afford admittance, have a lottery each year to determine who can enter the national park, or have park officials limit the number of guests entering the gate each day. Do these options seem reasonable to you? Why or why not? If Hetch Hetchy was restored and became part of Yosemite, many have wondered if more people would visit there and help reduce the flow of visitors to the more crowded parts of Yosemite. Currently, Hetch Hetchy is not an area that is visited by tourists on a regular basis like Yosemite. Do you think that might help with the congestion of visitors at Yosemite? Why or why not?
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MOS 5201 CSU Introduction to Safety Engineering Discussion
THESE (4) QUESTION Explored Hierarchy of Controls in the areas of walking and working surfaces, tools and machines, and ma ...
MOS 5201 CSU Introduction to Safety Engineering Discussion
THESE (4) QUESTION Explored Hierarchy of Controls in the areas of walking and working surfaces, tools and machines, and materials handling. Please further explore the hazards and their controls in the areas of pressure, ionizing radiation, and ventilation please see question attached.QUESTION 1Your quality control/quality assurance manager has requested your assistance in the testing and repair facility. One of the test procedures utilizes a radiation source that is emitting gamma radiation at a rate of 50 mrem/hour at a distance of 1 foot. This testing is done for approximately 2 hours per day, 2 days per week. The Occupational Safety and Health Administration (OSHA) has a PEL of 1.25 rem per quarter and 5 rem per year.Determine the employee's exposure for 1 year.Calculate the exposure rate if the employee was moved to a distance of 3 feet from the radiation source.Calculate the exposure rate of the employee if a 5 cm lead shield was installed between the source and the detector. The employee is working at a distance of 1 foot from the source. [µ for lead, (662 keV gamma ray) = 1.23cm-1]Your response must be at least 200 words in length.QUESTION 2There are several gas cylinders that are under pressure, which are located outside of the maintenance department. As the safety professional, you have been asked a couple of questions regarding this issue. Please provide the correct responses and discuss your recommendations for any control measures.The volume of the gas cylinder is 25.7 liters and exerts a pressure of 670 mmHg. If part of the gas is used, the pressure drops to 595 mmHg. What would be the remaining volume of gas?One of the cylinder's content is under pressure at 1900 psi (per the gauge) at 70°F. As the day heats up because of the sun, the temperature increases to 105°F. What is the pressure at 105°F?Your response must be at least 200 words in length.QUESTION 3The maintenance manager of your facility has asked you to evaluate a particular welding booth that utilizes a local exhaust ventilation (LEV) system to remove the contaminant at the source. The exhaust system does not appear to be drawing enough of the welding fumes away from the employees to reduce the iron oxide below the permissible exposure limit (PEL) of 10 mg/m3. During your investigation, you determine that the diameter of the duct system is 8 inches and has an air velocity of 350 fpm (feet per minute). The welding operation is performed at a distance of 1.5 feet from the exhaust opening. Determine the flow rate, and provide your recommendations on the control measures that could improve the capture of the iron oxide contaminant.Your response must be at least 200 words in length.QUESTION 4A process involves the removal of oil and other liquid contaminants from metal parts using a heat-treat oven, which has a volume of 15,000 ft3. The oven is free of solvent vapors. The ventilation rate of the oven is 2,100 cfm, and the safety factor (K) is 3. The solvent used in the process evaporates at a rate of 0.6 cfm (cubic feet per minute). The operator would like to know how long it would take the concentration to reach 425 ppm.Your response must be at least 200 words in length.
BIOL 1011 Measuring the Rate of Photosynthesis Lab Report
*Lab is not needed to complete this assignment* You are simply making notes based on facts as in what will happen in the s ...
BIOL 1011 Measuring the Rate of Photosynthesis Lab Report
*Lab is not needed to complete this assignment* You are simply making notes based on facts as in what will happen in the situations. Answer all questions and make notes for all statements. Please also fill in the attached document!PhotosynthesisBackgroundFigure 1. The mouse, Mus musculusCan a Mouse Survive in a Jar?Oxygen was discovered over 200 years ago when Joseph Priestley experimented with mice in jars. He closed a mouse in an airtight jar and, after a short time, the mouse collapsed. Priestley then closed a plant in an airtight jar and it survived for weeks. So he decided to combine the two. The mouse in the jar with the plant was able to survive long past the mouse alone in the jar.Photosynthesis was not explained during Priestley's lifetime, so he never found out that the plant in the jar generated oxygen through photosynthesis and that is why the mouse was able to survive. Comparatively, the mouse that collapsed had used up all the oxygen in the jar.PhotosynthesisHumans, like other animals, require food to generate energy. Plants, in contrast, produce their own food. They use the process of photosynthesis to use carbon dioxide (CO2) and sunlight from the environment in order to generate molecules of sugar. Sugar is further converted to chemical energy that plants need to sustain their existence.Photosynthesis has been used by organisms for millions of years. The first photosynthetic organisms were the ancestors of modern-day cyanobacteria. Photosynthesis takes sunshine, CO2 from the air, and some hydrogen atoms from water to produce two very important molecules — glucose (C6H12O6) and oxygen (O2).The basic formula for photosynthesis is:6CO2+6H2O⟶C6H12O6+6O2carbon dioxide + water ⟶ glucose + oxygenPhotosynthetic organisms are the foundation of every ecosystem because they take limited inputs and produce physical matter. In this role, they are referred to as producers. Organisms that consume producers are accordingly called consumers.Photosynthesis takes place inside chloroplasts, special organelles located in the cells of plants and other photosynthesizing organisms. Chloroplasts are green because they utilize the pigment chlorophyll. The primary light-absorbing organs of plants are the leaves. Although chloroplasts are located in cells throughout a plant, chloroplast density is by far the highest in the leaves. Between 440,000 and 790,000 chloroplasts can be found per square millimeter in the leaf of a plant.One of the byproducts of photosynthesis is oxygen, an essential molecule vital to the existence of humans and animals on Earth. Earth’s atmosphere is about 22% oxygen and most of the remainder is nitrogen. Humans and animals rely on plants as the source of their oxygen.Rate of PhotosynthesisThe rate of photosynthesis is affected by a number of factors:Light intensityTemperatureAvailability of waterAvailability of nutrientsThere is a maximum rate of photosynthesis that is constrained by the limits of these factors. For example, there is a value for light intensity above which the rate of photosynthesis can no longer increase. Similarly, increasing the temperature from 10 °C to 20 °C will increase the rate of photosynthesis, because enzymes in the plant will be closer to their optimal working temperatures, and molecules in the cells will move faster owing to increased kinetic energy. However, if the temperature is raised above a certain level, the rate of photosynthesis will drop as plant enzymes are denatured.Net Exchange of GasesIt is important to remember that while carrying out photosynthesis in the chloroplasts, the plant is also carrying out cellular respiration, which releases CO2. In this lab, you will measure the net rate of gas exchange for the combined processes of photosynthesis and cellular respiration.The CO2 for photosynthesis is supplied in this experiment by sodium bicarbonate dissolved in water. CO2 is much more soluble in water than oxygen is. More CO2 is used up by photosynthesis than is released by respiration. Therefore, it is expected that the net change in CO2 will be negative. This means that more CO2 will go into the plant than will be removed from the water.On the other hand, oxygen is not very soluble in water, but is produced during photosynthesis. Therefore, it is expected that its net change will be positive. This means that the plant produces more oxygen during photosynthesis than it consumes in respiration.Overall, the gas being produced and measured is oxygen.A plant’s rate of respiration can be determined by measuring the rate of oxygen uptake during periods of darkness, when no photosynthesis takes place. Again, oxygen's insolubility in water helps with this measurement. As the plant respires, oxygen is removed from the gas in the system. At the same time, CO2 is released but remains dissolved in the water. The total change in the volume of the solution is negligible.About This LabIn this lab, you will measure the rate of photosynthesis in the aquatic plant Elodea under various conditions. You will measure the rate of photosynthesis by observing gas production. You will explore the gas exchange of the plant with its environment in both light and dark conditions and observe if photosynthesis and respiration take place in parallel when light is present.You will modify the light source intensity to test how the rate of photosynthesis changes depending on the intensity of light falling on the leaves of the plant. You will also test the effect of temperature on the rate of photosynthesis.ExperimentsOpen the simulation by clicking on the virtual lab icon below. The simulation will launch in a new window.You may need to move or resize the window in order to view both the Procedure and the simulation at the same time.Follow the instructions in the Procedure to complete each part of the simulation. When instructed to record your observations, record data, or complete calculations, record them for your own records in order to use them later to complete the post-lab assignment.ProceduresExperiment 1: Measuring the Rate of PhotosynthesisPart 1: Set-upTake a plant light box from the Instruments shelf and place it on the workbench.Take a 250 mL Erlenmeyer flask from the Containers shelf and place it onto the workbench.Take a branch of Elodea from the Materials shelf and add it to the Erlenmeyer flask.Add 100 mL of 0.1 M sodium bicarbonate solution from the Materials shelf to the Erlenmeyer flask. Make sure the solution covers the branch, as Elodea is a submergent aquatic plant and acquires carbon dioxide from the water. Record the plant name and the solution the plant is in to reference later.Place the Erlenmeyer flask into the plant light box. Set the temperature of the plant light box to 20 °C, which is around room temperature. Record the temperature to reference later.Switch the plant light intensity of the plant light box to 5, the maximum. This setting is located next to the gray Start button in the upper right corner of the plant light box. Record the plant light intensity to reference later.Set the timer to 120 minutes.Part 2: Collecting Oxygen Produced by the PlantThe rate of photosynthesis can be measured by collecting the oxygen produced by the plant.Take a gas syringe from the Instruments shelf and place it onto the plant light box. Record the initial volume in mL of gas in the syringe at 0 min of the experiment (countdown timer reads 120 min) to reference later. To see the volume, double-click on the gas syringe. Press the gray Start button in the upper right corner of the plant light box. After 30 simulated minutes in the plant light box (countdown timer will read 90 min), press the lab pause button in the lower left corner of the lab (Figure 1) to note the gas volume in the syringe.Figure 1. Lab Pause ButtonAfter recording the simulated time and gas volume to reference later, press the lab play button (Figure 2) to resume the experiment.Figure 2. Lab Play ButtonRepeat this pausing and playing sequence to note and record the gas volume in the syringe after:60 simulated minutes (countdown timer reads 60 min)90 simulated minutes (countdown timer reads 30 min)120 simulated minutes (countdown timer reads 0 min)When the door of the plant light box opens to indicate this run is done, make sure to leave everything in place for the next experiment. Experiment 2: Respiration in the DarkChange the light intensity of the plant light box all the way down to 0 for dark conditions. Record the plant light intensity and temperature settings to reference later.Set the timer to 120 minutes. Record the initial volume at 0 min of the experiment (countdown timer reads 120 min) of gas in the syringe to reference later.Press the gray Start button.Using the lab pause and play buttons as needed, record the syringe's gas volume after:30 simulated minutes (countdown timer reads 90 min)60 simulated minutes (countdown timer reads 60 min)90 simulated minutes (countdown timer reads 30 min)120 simulated minutes (countdown timer reads 0 min)When the door of the plant light box opens, move the flask to the waste to empty it.Place the empty flask in the sink.Double-click the gas syringe and reset the plunger. Make sure the volume goes back to 0.00 mL.Experiment 3: Effect of Light IntensityRepeat the set-up outlined in Experiment 1, Part 1, steps 2 – 9. However, this time set the plant light intensity to 4. Record the initial volume of gas in the syringe at 0 min of the experiment (countdown timer reads 120 min) to reference later.Press the gray Start button, then use the lab pause and play buttons to note and record the syringe's gas volume after:30 simulated minutes (countdown timer reads 90 min)60 simulated minutes (countdown timer reads 60 min)90 simulated minutes (countdown timer reads 30 min)120 simulated minutes (countdown timer reads 0 min)Record the plant light intensity and temperature settings to reference later.When the door of the plant light box opens, move the flask to the waste to empty it.Place the empty flask in the sink.Double-click the gas syringe and reset the plunger. Make sure the volume goes back to 0.00 mL.Repeat the procedure outlined in steps 1 – 7 for the following plant light intensity settings:321Experiment 4: Effect of Environmental TemperatureSet the plant light intensity of the plant light box to 5 and the timer to 60 minutes. Record the light intensity setting to reference later.Take a 250 mL Erlenmeyer flask from the Containers shelf and place it onto the workbench.Take a branch of Elodea from the Materials shelf and add it to the flask.Add 100 mL of 0.1 M sodium bicarbonate from the Materials shelf to the flask.Place the flask into the plant light box.Set the temperature of the plant light box to 10 °C. Record the temperature setting to reference later.Record the initial volume of gas in the syringe at 0 min of the experiment (countdown timer reads 60 min) to reference later.Press the gray Start button.Record the volume in the gas syringe after 60 simulated min (countdown timer reads 0 min) to reference later.Move the flask to the waste to empty it.Place the empty flask in the sink.Double-click the gas syringe and reset the plunger. Make sure the volume goes back to 0.00 mL.Repeat steps 2 – 12 for two additional temperatures:30 °C40 °CClear the bench of all materials, containers, and instruments, then return to your course page to complete any assignment for this lab.
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