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chem--buffers

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Chem
.1 M HCl + .1 M NaCl .1 M HF + .1 M NaF .1 M HBr + .1 M NaBr Which of the above would be considered buffers?

Chem Lab
Can the NH3/NH4Cl system be sued to prepare a buffer of a pH 9.5? why or why not? Can it prepare a buffer of pH 5? There were two buffers, 0.2 M and 0.1M.

Chemistry
3 buffers in the human body and what are their conjugate acid-base pairs? I have Bicarbonate Buffer, Phosphate/Ammonia Buffer, and Protein Buffers, where my confusion lies in what would be there conjugate acid base pairs.......

chem( buffers)
Does water have a high buffering capacity? Why is it important to know it buffering capacity of water?

Chemistry
An industrial chemist studying bleaching and sterilizing prepares several hypochlorite buffers. Find the pH of the following buffers. (a) 0.090 M HClO and 0.090 M NaClO (b) 0.090 M HClO and 0.135 M NaClO (c) 0.135 M HClO and 0.090 M NaClO (d) One liter of the solution in part...

biochemistry with more info that was needed
Calculate the weight of the buffers you will use to make the buffers for Part A for all the buffer possibilities listed under procedures in Part A, step 1. In other words, how many grams do you need to make 100 mL of a 0.1 M buffer? Buffer pKa1 pKa2 pKa3 formula wt.(g/mol) ...

Chemistry Buffers
Write reactions showing how each of the following buffers would neutralize added HCl. HF and NaF Express your answer as a balanced chemical equation. Identify all of the phases in your answer. HC2H3O2 and KC2H3O2 Express your answer as a balanced chemical equation. Identify ...

Chem--buffers
Explain why a mixture formed by mixing 100 mL of 0.100M CH3COOH and 50 mL of 0.100M NaOH will act as a buffer? in adittion to this, how do you identify if a an aqueous solution is a buffer solution, such as a solution with an acid and a base, but no common ion? is it possible ...

Chemistry (repost)
Which of the following pairs of substances, when mixed in any proportion you wish, can be used to prepare a buffer solution? 1)NaCN and NaOH 2) HCl and NaOH 3) HCN and NaOH 4)HCl and NaCN 5) NaCN and HCN is the answer 1 and 5?? chem - DrBob222, Sunday, April 10, 2011 at 1:28am...

chemistry
How do basic and acidic buffers resist pH ?

Chem 2
A popular buffer solution consist of carbonate (CO3 2-) and hydrogen carbonate (HCO3-) conjugate acid-base pair. Which, if any of the following such buffers has the highest buffer capacity? A. 0.9M CO3 2- and 0.1M HCO3- B. 0.1M CO3 2- and 0.9M HCO3- C. 0.5M CO3 2- and 0.5M ...

Steph
Buffers work by converting _____ to ____.

chemistry
if there were no buffers in our blood, what would happen when we drank something acidic?

Chemistry
Name 3 buffers that exist in the human body? Include the conjugate and acid base pairs

chemistry
1. Compare the effects of adding the strong acid & base to the pH of water vs. the acetate and phosphate buffers.

Chemistry
Which two conjugates could not undergo hydrolysis to act as buffers? C6H5COO- H2PO4- NH4+ ClO4- C5H5NH3+ F- Br-

chem--buffers
Calculate [H30+] in a solution that is 0.0525M HCl and 0.768M NaC2H3O2. Ka(HC2H3O2)= 1.8 x10^-5. the way i did it is that i used the given molar of HCl to find the moles of Hydronium in the acid, and then i used that to find the moles of OH- in it, using kw. then through the ...

chemistry
how do you do acids/bases, oxidation, buffers, and Boyle's Law. what are the rules for each, can u give me an example for each and explaining how you get the answers, because i'm confused on how you do these.

Chemistry - buffers
Laborant got a task to make a buffer, which pH = 8.00. Which same concentration solutions and which ratio would you suggest him to mix?

College Chemistry
Calculate the ratio of NaF to HF required to create a buffer with pH=3.95. Also, can you please explain in a nutshell the whole concept of buffers? Thanks!

E.M.U
For the same solution components as in part (f), buffers are prepared with a total concentration of NH3 + NH4Cl = 0.10 M. The pH values are 8.0, 8.5, 9.0, 9.5, 10.0, 10.5, and 11.0. Find the molar solubility of CdS in these solutions

buffers
9.00mL of 1.10M CH3COOH and 1.00mL of 0.900M CH3COO- what is the pH?

chemistry - buffers
what mass of sodium acetate should be dissolved in 1.00L of acetic acid, 0.150M concentration, in order to produce a buffer with pH = 4.5?. Ka of CH3COOH = 1.8x10^-5

Chemistry
Which four salts could undergo hydrolysis to act as buffers if added to their parent acid or base? KF KH2PO4 NaCl KBr NaClO4 C5H5NH3Cl NH4Cl

bio chemistry
calculate the PH of each of the following buffers prepared by placing in 1.0 L of solution 0.10 mol NH3 and 0.10 mol of NH4CL

Electronics
Here we examine noise in a digital channel between an AND gate and an inverter shown in Figure 16. The channel has a length of D=30m and noise is added in at the rate of 0.6Vm. To correct for that noise, we introduce non-inverting buffers into the channel. The purpose of a ...

chemistry
Since amino acids and proteins carry proton-accepting and proton-donating groups, they can act as a.buffers b.enzymes c.isomers d.vitamins

Chemistry
Which three substances' conjugates cannot act as buffers? i.e. There are no weak conjugates in the compounds. NH3 C6H5COOH H3PO4 NaHCO3 C5H5N HBr HF NaOH HClO4

Chemistry (buffers)
Say, for example, that you had prepared a Buffer C, in which you mixed 8.203 g of sodium acetate, NaC2H3O2, with 100.0 mL of 1.0 M acetic acid. a. What would be the initial pH of Buffer C? HOW???????

Chemistry
I was given a list of 14 different solutions, and My homework question asks which of the solutions exhibit the common-ion effect and which ones are buffers? But, how would I be able to tell???

Biology
The question is exactly like this: The nurse is reviewing a client's blood ph level. which of the systems in the body regulate blood Ph? select all that apply A.buffers b.respiratory c.renal d.cardiac

Chemistry- Buffers
a buffer is prepared by mixing .208 L of 0.452 M HCl and 0.5 L of 0.4 M sodium acetate. When the Ka= 1.8 x 10^-5 I figured out that the pH= 4.74 but then it asks how many grams of KOH must be added to the buffer to change the pH by .155 units?

Chemistry - buffers
Two burettes are filled with solutions: one with 0,1OM CH3COOH solution, second with 0,15M CH3COONa. How many milliliters each solution will need to make 20mL of solution, which pH=4.85

Science- Chemistry
How many grams of sodium acetate( molar mass 82.03 g/mol) must me added to 1.00L of a 0.200M acetic acid solution to form a buffer of 4.20?Ka value for aceic acid is 1.8 x 10^-5. How do I go about finding the grams from the given information? http://www.chembuddy.com/?left=pH-...

chemistry
Which one of the following mixtures is suitable for making buffers? 1 H3PO4 and NaH2PO4 2 Na2CO3 and NaHCO3 3 NH4Cl and NH3 a. 1 only b. 2 only c. 3 only d. 1 and 2 only e. 1, 2, and 3

Chemistry
If equal volumes of the following are combined, would they form buffered solutions? Why or why not? .1M HF and .05M NaF I'm am a bit confused about how I can figure out if these will form buffers or not, so I'd really appreciate it if someone could explain it to me. Thanks.

Chemistry
If equal volumes of the following are combined, would they form buffered solutions? Why or why not? 1) .1M NaC2H3O2 and .1M HF 2) .1M HF and .05M NaF I'm am a bit confused about how I can figure out if these will form buffers or not, so I'd really appreciate it if someone ...

Chemistry
Please help! If equal volumes of the following are combined, would they form buffered solutions? Why or why not? .1M HF and .05M NaF I'm am a bit confused about how I can figure out if these will form buffers or not, so I'd really appreciate it if someone could explain it to ...

Biochem
HEPES, is a commonly used component of physiological buffers. The PKa of the protonated amino group of HEPES is 7.55 at 25C. Describe the preparation of 1.00L of 0.100M HEPES buffer, pH 8.00, from the sodium salt of the basic form of HEPES (MW 260.3), .0M HCL and deionized water

Chemistry -buffers.
The pH of an arterial blood sample is 7.15. upon acidification of 10 ml of the plasma 5.91ml of CO2 is produced at standard temperature and presure. Calculate-a) total CO2 in the specimen b)the individual concentration of disolved CO2(H2CO3) and HCO3- c)The partial pressure of...

chemistry
All of the following acid-base pairs are examples of buffers EXCEPT: (Question from "Cracking the MCAT, 2010-2011 edition" by The Princeton Review) HCl/NaCl CH3CO2H/NaCH3CO2 HF/NaF H2CO3/NaHCO3 I chose ch3co2h/nach3co2

Biology
I know that the phosphate [cells] and sodium barcarbonate [blood plasma] buffer systems are two examples of biological buffers; however, i am writing an essay for bio and i need a third example. does anyone know of a third biological buffer system?

Biochemistry
Sorry! HEPES, is a commonly used component of physiological buffers. The PKa of the protonated amino group of HEPES is 7.55 at 25C. Describe the preparation of 1.00L of 0.100M HEPES buffer, pH 8.00, from the sodium salt of the basic form of HEPES (MW 260.3), 6.0M HCl and ...

Chemistry
Which of the following pairs would make a good buffer? A. H2C2O4 and HC2O4- B. HNO3 and NO3- C. NaOH and NaCl D. HCl and NaOH Would it be C? I think I remember learning about these in a lesson about buffers, hence why my instinct is to go with C...

chemistry buffers
What molar ratio of HPO4 2- to H2PO4 - in solution would produce a pH of 7.0? Phosphoric acid (H3PO4), a triprotonic acid, has pKa values: 2.14, 6.86, and 12.4. Only one of the pKa values is relevant here. how do i know which pka value to use.. please explain

chem
what are the other practical applications of Analytcal chem on being a medical technologist?

chemistry
can you please give me some practical applications of qualitative chem and quantitative chem...

Biology(Anatomy&Physiology)
1)Which group of organic molecules makes up your genetic code 2)A substance which tends to resist a change in the pH of a solution is called a 3)Which buffers is the most common in the body 4)Which of molecules is primarily made of CHON 5)Which is the building block or monomer...

Chemistry
Buffers- Common Ion effect IS this Correct Calculate the pH of a aqueous solution containing 0.15 M HNO2 and 0.20 M NaNO2 (aq). The Ka of nitrous acid is 4.0*10^-4. HNO2 + H20 <--> NaNO2- + H30^+ Inital 0.15 0.20 X Final 0.15 0.20 Ka= [H30+][NaNO2]/ [HNO2] 4.0*10^-4 = [...

chemistry (buffers)
How can weak acid nitrous acid HNO2 form a buffer solution with equal concentrations and volumes with weak base NH3? I thought that buffer solutions only occured between weak acids and strong bases or vice versa. The example above as two weak soltuions.

chem- drbob222 please help
my original question was: how do i figure this out?? How much heat does your body lose when 2.46 g of sweat evaporates from your skin at 25°C? chem - DrBob222, Tuesday, February 22, 2011 at 10:52pm q = mass water x delta Hvaporization. chem - Rebekah, Wednesday, February 23, ...

biochemistry
A 20.0 mL sample of gastric juice was taken from a patient suspected of having hypochloridia (low stomach acid). The sample was taken several hours after a meal so there was no ingested food or drink, and it was assumed no buffers were present. The sample required 6.3 mL of 0....

Science
what is the importance of ph to biological systems in the human body? I have an answer but is there anything else I could include and is my answer justified? My answer: Changes in the ph could be harmful, Natural buffers prevent rapid or large changes in the pH of living ...

Chemistry
Sodium methanoate, NaHCOO, and methanoic acid, HCOOH, can be used to make a buffer solution. Explain how this combination resists changes in pH when small amounts of acid or base are added. Buffers kind of confuse me and I'm not sure how to start this. Can someone help me to ...

chemistry
A buffer is prepared by dissolving .0250 mol of sodium nitrite, NaNO2, in 250.0 mL of .0410 M nitrous acid, HNO2. Assume no volume change after HNO2 is dissolved. Calculate the pH of this buffer. My book does a poor job of explaining buffers and I'm really lost on the concept...

chem
so i posted this question yesturday and got some help. which is the stuff below. can you look at the last thing i said which was the answer i got by doing what DrBob222 said to do and tell me if its correct.(the question is the first section) thanks chem - hannah, A salt ...

chem chem
hi does anyone know what the VSPER theory is

chem
if a car produces 81g of {\rm CO_2}, how many grams of {\rm O_2} are used up in the reaction? the complete chem reaction is C2H6O+3O2--->2CO2+3H2O

Analytical chemistry
What is a pH of 20 mL of 0.08 M NH3 added to 40 mL of 0.04 M HCl? NH3 + HCl = NH4+ + Cl- c(NH3)=(0.02L * 0.08M)/0.06L= 0.02667 M c(HCl)=(0.04L * 0.04M)/0.06L= 0.02667 M c(NH4+)=c(HCl) Kb=[NH4+][OH-]/[NH3] Kb=1.76*10^(-5) So i tried to calculate it like this: Kb=[OH-] pOH=4....

Chem Help!
I really need help with this question for my chem H.W. 1) On a summer day in Breckenridge, Colorado, the atmospheric pressure is 525 mm Hg. What is this air pressure in atmospheres? (round to the hundredths place) atm

Biology
The following chemicals have the indicated formula weight Surcose = 342.3g; Potassium dihydrogen=136.09; and Tris=121.14 Also the following solution already made: 20%SDS, 5M NaCl, 500mM EDTA. You have a 40% glycerol solution, and 10X TBE. List the step to make the following ...

Molecular cell Biology
The following chemicals have the indicated formula weights:Sucrose-342.3,Potassium dihydrogen phosphate(KH2PO40-136.09,Tris -121.14.You also have the following solutions made:20%SDS,5M NaCl,500mM EDTA.You have a 40%glycerol solution and 10X TBE.List the steps to make the ...

Chem- bobpursley
What mass of protons would be required to just neutralize the charge of 1.5 g of electrons? my teacher said .0015kg times 1e-/.00091e-27kg times 1pt/1e- times 1.67262e-27 over 1 p chem - bobpursley, Tuesday, September 21, 2010 at 6:48pm That is what I would do also. But I ...

chem - br bob is this right
What is the pH of a solution prepared by adding 4.000 grams of NaOH to a 50.00 mL of a buffer that is 2.00 molar both in acetic acid and sodium acetate? (Assume final volume is still 50.00 mL) * chem - DrBob222, Wednesday, April 21, 2010 at 10:52pm * chem - phil, Wednesday, ...

Chem
What causes dispersion forces? Disperson forces are caused by an unsymettrical distribution of charge in the molecule, causing a net electric force. http://www.chem.purdue.edu/gchelp/liquids/disperse.html

Gen Chem II
Thanks for the information Dr. Bob. Would you be able to work it out so that I can actually see the steps with the numbers and follow from there. The question was on Vitamin K from Sunday at 2:44pm which you answered at 3:45pm. Thanks again. I am looking to get a tutor since I...

AP CHEM
A secondary alcohol results from the attachment of a hydroxy group to which carbon atom? C | <---GIVEN STRUCTURE C1-C2-C3-C4 A) C1 B) C2 C)C3 D)C4 Answer is C! I have to explain why, but the teacher never taught us anything about organic chem. So please explain!

College/education class
What are the most effective and ineffective uses of objective assessments for instructors and learners? What is your view on the relative advantages and disadvantages of using objective tests? How might you incorporate objective assessments in your instructional design in the ...

Dr.Bob222 Chem
I believe that you are correct because you have more experience in G-chem then I have. But how does doubling the reaction rate double the k value? Isn't k just a constant for a particular reaction?

chem org
dipole-dipole means? and diff between non polar and polar? is it really part of organic chem?

Chem 1
Write a chemical equation that shows how acid rain H2SO3 was produced from SO2 gas and water in a zip sealed bag? My chem. teacher never explained how to do this and I have several other questions on this type of subject. If you could help me out it would help me tremendously...

physics vs. Chem
Doesnt physics seem to be harder than chem? Anyone?

Advice...about chemistry degree Dr.Bob
Based on the question topic posted by Britney below titled:In your opinion (your answer to this reminded me of something) (I posted the same thing there but I thought it was improper to piggyback on that post so I posted this under a new topic) I don't know where to start but ...

chemistry lab
Could someone help me with this? i am tired of it. here is my data from lab: Buffer1: HPO4- weight 3.412g; original pH Buffer 2: HEPES wt: 1.090g original pH 10.08 buffer1: pH of 0.1M: 7.5; pH of 0.01: 7.72; pH of 0.001M: 7.87 buffer2: PH of 0.1M: 7.5 ph of 0.01 M: 7.42 pH of ...

Chemistry- Acids and Buffers
Cyanic Acid is a weak acid HOCN + H2O <--> H3O+ +OCN- ka= 3.5*10^-4 a) if 2.5ml of 0.01 M cyanic acid solution is added to 25.0 ml of a formis acid buffer with ph = 3.70, what is the ratio of [OCN-]/[HOCN] in the resulting solution? b) determine the pH of a 0.500 M ...

sand bath (chem)
what are disadvantages and advantages of using a sand bath to heat something in chem?

chem
What is another name for cardamist? Please write the formula and a link to its structure. See http://antoine.frostburg.edu/chem/senese/101/consumer/faq/what-is-cardamist.shtml

Chem - DrBob222 & drwls
Just want to say thanks to you guys for the help you gave me during the last couple of months. It was all in preparation for the National Chemistry Test and I just received word I have been selected to be in the running for the National Chem Team. Thanks again.

CHEM organic chem
i am really confused! i am doing the production of ethene from fractional distillation and i understand the whole concept of it what i don't get is how i can write a balanced eqn to show how ethene can be produced from C14H30 (tetradecane?!) i did C14H30 ------> C7H14 + ...

CHEM organic chem
i am really confused! i am doing the production of ethene from fractional distillation and i understand the whole concept of it what i don't get is how i can write a balanced eqn to show how ethene can be produced from C14H30 (tetradecane?!) i did C14H30 ------> C7H14 + ...

chem equations
could someone tell me how i could solve this chem equation CH4 + NH3 +O2...> HCN +H20 AND USE THE LOWEST WHOLE NUMBER COEFFICIENT i WOULD BE GRATEFUL FOR ANY POINTERS Try these coefficients. 2,2,3==>2,6 Hi bex heres a little more help for you. Answer is 2CH4+2NH3+3O2--&...

Chem
Are: Ba(NO3)2, Ti)2, MgI2, and Ca(CH3COO)2 soluble or insoluble in H2O @ 25degrees C? Here is a site that lists the solubility rules. You should know this table; eventually you will want to know it so well that it is memorized. If you still have questions after viewing this ...

chem help
im doing a graph for chem lab with excel. my classmate created a graph with these coordinates: X: 3.50 X10^-3 3.14X10^-3 3.28X10^-3 Y: -11.7 -8.96 -9.75 They got R2=0.998 but i got y = -3074.9x R² = 0.6291 why is it wrong. im desperate please help! screen shot of my graph: ...

Chemistry
Ok, so in my gen chem 1 class, the teacher showed us that ethanol would not dissolve a sugar cube while water dissolves a sugar cube easily. No explanation was given, she just told us we would find out in gen chem 2. Here i am in gen chem 2, and the same thing is shown to us ...

chem/science
Please predict what will happen. Im not very good in chem. Iron metal and pb(NO3) Lead metal and Mg(9NO3)2 Copper metal and AL(NO3)3 Lead metal and AgNO3

Chem
A 10.0% by mass H2SO4(aq) solution has a density of 1.07 g·cm-3. How many milliliters of solution contain 8.34 g of H2SO4? What mass (in grams) of H2SO4 is in 248 mL of solution? It's been a while since I have had a chem class...so sorry if this seems really easy I just don't...

Chem
Calculate the expected volume of hot water that would be required to dissolve 0.15g of benzoic acid, vanillin, phthalic acid, salicyclic acid? You don't need to do all or any of them. I just need to know what formula to use and what to sub in and I can do the rest myself. I ...

organic chemistry
whats the difference between inorganic chem and organic chem? im really confuse because mrs. white told us inoraganic is about ionic bonds while organic is about covalent bond. what is the difference between the twooo? please help me

I have a question concerning Spring Semester
Im a freshman in college and I just took Chem1, Trig, and Drama (12units). I am planning on taking Chem2, Pre-Calc, and Art1 for spring sem. (13units). I'm not sure if this is too much to take for next semester considering two five unit classes or should I add another class? ...

Chemistry, pH, Buffers
Please help!! Given this data: mass of unknown acid 1.4671g Volume of NaOH used in titration 18.47mL Concentration of the NaOH used 0.2403M pH of the original acid solution 2.16 pH of the final acid solution 3.49 Show me how do I calculate the Ka of the unknown acid and the ...

Gen Chem
For my chem class I have 3 elements and have to find what they are used for today or an interesting fact. I have looked but I can't really fin anything. My elements are: Cobalt,Thulium, and Roentgenium I found that cobalt is used in money (nickels, quarters, and dimes, but ...

Chemistry, Buffers, pH
Hi could someone please help me in the next 5 minutes with this question: Given this data: mass of unknown acid 1.4671g Volume of NaOH used in titration 18.47mL Concentration of the NaOH used 0.2403M pH of the original acid solution 2.16 pH of the final acid solution 3.49 Show...

High school AP chem
The solubility of Mn(OH)2 is 3.04 x 10^-4 gram per 100 ml of solution . A) write the balanced chem equation for Mn(OH)2 in aqueous solution B) calculate the molar solubility of Mn(OH)2 at 25 degrees celcius C) calculate the value of the solubility product constant, Ksp, for Mn...

Chem
The solubility of Mn(OH)2 is 3.04 x 10^-4 gram per 100 ml of solution . A) write the balanced chem equation for Mn(OH)2 in aqueous solution B) calculate the molar solubility of Mn(OH)2 at 25 degrees celcius C) calculate the value of the solubility product constant, Ksp, for Mn...

Final-Chemistry
I have finals coming up in a week and a half. I know I should have started studying earlier, but I just had an exam in my chem class and was focused on getting the information for that exam mastered before I started studying for the final. Now, I'm overwhelmed. I have no idea ...

General Chem
So for Chem we have to answer a question asking why graphing is a more accurate method for measuring density than manually calculating the density. I originally thought that manually calculating was better, but my teacher told me that I would have to back that up with a lot of...

drying agent in chem
Is it advisable or not to leave a solution in drying agent for a few days? ~I did this ..since my chem lab instructor said to but I'm not sure I believe him. He sounded unsure of himself when he answered me. solution: methylene chloride (extracting oil of caraway) drying agent...

Chemistry
Describe how a buffer behaves. Your description should include an explanation of why the addition of NaOH to the HAc solution formed a buffer. What happens to the pH when a small quantity of a strong acid or base is added to a buffer solution? What happens to the pH of the ...

Chemistry
Select the statements that correctly describe buffers.? 1) The pH of a buffer solution does not change significantly when any amount of a strong acid is added. 2) The Ka of a buffer does not change when any amount of an acid is added to the buffer solution. 3) The pH of a ...

Math
in a class of 60 students 30 like maths 25 like physics 30 like chemistry. if 10 like both physics and maths 5 like maths and chem and 5 like phy & chem and 3 like all the subjects. find student like none of subject of if 100 students were surveyed

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