PLEASE HELP Chemistry Related Math/Hydraulic Problems I Can't Get

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In summary: For the pressure problem, we need to use the formula P = ρgh, where P is pressure, ρ is density, g is gravity, and h is height. In this problem, we are given the height of the reservoir, 16m, and the fact that it is half full. This means that the height of the water in the reservoir is 8m. We also know that the density of water is 1000 kg/m^3. Plugging these values into the formula, we get a pressure of 78,400 Pa, which is equivalent to 78.4 kPa.4. For the chlorine dosage problem, we need to use the formula C = Q/V, where C is concentration,
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Underdog_85
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URGENT PLEASE HELP! Chemistry Related Math/Hydraulic Problems I Can't Get

Got a test tomorrow on this stuff. If I know how to attack these problems, I will be ok.

1. A water plant treats a flow of 9.0 ML/d. the Mix chamber is 0.75m x 0.75m and the depth of water is 1.0m. Flocculation basin is 15m x 5m x 2.5m. What is the flocculation time in minutes?

3. The Attempt at a Solution :
(Answer is 30 minutes)
9.0ML/d = 375kl/h
15 x 5 x 2.5 = 187.5m^3 = 187 000 L
.75x.75x1 = .56m^3 = 560 L

I'd write down what I actually did, but it is nowhere even close. I keep getting numbers much less or wayyyyyy higher.

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1. the Chlorine demand of a certain water is 3.0mg/L. If the plant operator adds 40lb's of chlorine gas to treat 1.0 million gallons of water, what should be the chlorine residual in mg/L?

2. My attempt
I thought I was right, I still think I am. It says the answers is 1.8 but it just doesn't seem right to me.

CONVERSIONS:
1 000 000 gallons --> 3 785 411.78 L
40 lb ---> 18. 143 kg ----> 18 143 000 mg

18 143 000mg/3 785 411.78 L = 4.79mg/L

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3. A storage reservoir is 12m wide and 16m high. What is pressure at the bottom of the reservoir, when it is half full?

my attempt
i got it right, but somehow i think it was a fluke.

16m/2 = 8m
8m x 9.81 = 78.9 = 80 kPa(final answer)

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4. you are required to provide a 2.5mg/L chlorine dosage to water pumped from a well at a rate of 35L/s/ On the well site, you have 200L capacity hypochlorite tank containing 12% chlorine solution. If the feed pump is properly calibrated, how many litres of chemical should be used per hour?

my attempt
Not even worth showing you guys. It is so wrong it is funny. I get a massively high number. The final correct answer is 2.6

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5. What is the metres of head at the discharge side of the pump that is pumping at a pressure of 93psi?

my attempt
93 x 9.81 = 912 <----- so wrong. answer is actually 65.
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I realize for a lot of people these questions are simple. For me, I haven't done this stuff in years and I really don't know how to act these 5 types of problems. However, on the test, these are the types of questions I will get. So if I know how to attack them I will be ok. I hope you people can help me out! Thanks alot
 
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I understand that you have an upcoming test and are struggling with some chemistry related math and hydraulic problems. I am happy to help you understand how to approach these problems so that you can feel more confident and prepared for your test.

1. For the flocculation time problem, it is important to first understand the units being used. The flow rate is given in ML/d (million liters per day) and the volume of the mix chamber and flocculation basin are given in cubic meters (m^3). In order to find the flocculation time in minutes, we need to convert all units to a common unit. Let's convert the flow rate to liters per hour (L/h) by multiplying by 1000, and then convert the volumes to liters by multiplying by 1000. This gives us a flow rate of 9,000,000 L/h, a mix chamber volume of 560,000 L, and a flocculation basin volume of 187,500,000 L. Now, we can use the formula t = V/Q, where t is time, V is volume, and Q is flow rate, to find the flocculation time in hours. Once we have the time in hours, we can convert it to minutes by multiplying by 60. This should give you the correct answer of 30 minutes.

2. For the chlorine residual problem, it is important to remember that chlorine demand is the amount of chlorine needed to treat a certain volume of water, while chlorine residual is the amount of chlorine remaining in the water after treatment. In this problem, we are given the chlorine demand of 3.0 mg/L and the amount of chlorine added, 40 lb (which is approximately 18,000 mg). We need to find the residual in mg/L, so we need to divide the amount of chlorine added by the volume of water treated. As you correctly did, we need to convert gallons to liters, giving us a volume of 3,785,411.78 L. Now we can divide the amount of chlorine added by the volume to get a residual of 4.75 mg/L. This is close to the given answer of 1.8, but not exactly the same. It is possible that the given answer is rounded or there may be a mistake in the problem. It is always important to double check your work and make sure your answer makes sense in the context of the problem.

3
 

1. What are some common types of chemistry related math problems?

Some common types of chemistry related math problems include calculating molar mass, converting units, balancing chemical equations, and solving stoichiometry problems.

2. How can I improve my understanding of chemistry related math problems?

One way to improve your understanding of chemistry related math problems is to practice regularly. You can also seek help from a tutor or join a study group to work through problems together.

3. What are some common mistakes to avoid when solving chemistry related math problems?

Some common mistakes to avoid when solving chemistry related math problems include not paying attention to units, not double-checking your work, and not understanding the basic concepts involved in the problem.

4. How can I apply math to hydraulic problems in chemistry?

Math is used in hydraulic problems in chemistry to calculate pressure, flow rate, and other variables involved in fluid dynamics. By understanding the basic principles of math and how they apply to fluids, you can solve hydraulic problems more effectively.

5. What resources are available to help me with chemistry related math and hydraulic problems?

There are many resources available to help with chemistry related math and hydraulic problems, such as textbooks, online tutorials, and practice problems with solutions. You can also consult with a teacher, tutor, or fellow student for assistance.

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