Introductory Courses

Can someone explain how to do a dilution problem in chemistry?

Can someone explain how to do a dilution problem in chemistry?

i understand that dilution is adding water to an acid to reduce its strength.

but every time i try a dilution problem in chemistry, i dont know where to start! is there an equation or rules to follow to do this?

tonih79   387   3 Replies

nursing11

Can someone explain this enzyme prac to me?

Can someone explain this enzyme prac to me?

Hi,

We did an experiment in bio where we put 1.25g pieces of liver in 5 different test tubes, and then poured a solution on them.  The solution for the first test tube was 20% hydrogen peroxide, 40% hydrogen peroxide, 60%, 80% and the

WCH990   687   3 Replies

padre

Can someone help explain why is the theoretical yield of a reaction is seldom accomplished in the laboratory?

Can someone help explain why is the theoretical yield of a reaction is seldom accomplished in the laboratory?

Can someone help explain why the theoretical yield of a reaction is seldom accomplished in the laboratory? Thanks!!!

JUJUBEEM   1434   1 Reply

juju2744

Can someone help me explain gel electrophoresis in relation to amino acids?

Can someone help me explain gel electrophoresis in relation to amino acids?

Can someone help me explain gel electrophoresis in relation to amino acids?

buk280forlife   1537   2 Replies

vcm2223

Can someone help me with my chemistry pre-lab, Thanks!!!?

Can someone help me with my chemistry pre-lab, Thanks!!!?

I have not idea how to do that, thanks for your time to help me.

A saturated aqueous solution of slightly soluble salt, barium iodate [ Ba(IO3)2] was prepared and titrated with sodium thiosulfate. Based on the data tabulated below, calculate the ind

Rima5879   438   1 Reply

darkspirt

Can someone help me with the a dilution of HCl question?

Can someone help me with the a dilution of HCl question?

It asks: How to make a 100mL of the 0.025 M HCl solution by dilution of the 1.0 M HCl solution that is given.

I really tried and the answer I got was use 0.0025 moles of HCl for 100 ml? Am I on the right track?
If I am, what how many mL is 0.0025 m

tonyagodsey   306   3 Replies

rimazx

Can someone please explicitly derive the answer ?

Can someone please explicitly derive the answer ?

In a hospital lab,10mL of gastric juice,obtained after several hrs of meal was titrated with 0.1M NaOH to neutrality;7.2mL of NaOH was required.The patients stomach had no ingested food or drinks.Assume that no buffers were present.What was the pH of

smileyprincess111   285   1 Reply

tomy_uos

Can someone please help me with the stage of mitosis?

Can someone please help me with the stage of mitosis?

Also - how does mitosis differ from meiosis?  I looked in my textbook and it's so confusing.  I just want a brief and concise answer.  Thank you!

Please give me a "good post" rating!

schung7   3220   9 Replies

NeoshadowXC

Can someone please help with chemistry problems?

Can someone please help with chemistry problems?

The following question is part of my chemistry lab and I am having trouble answering it because we don't have a book. Thanks for any help!!

1) (a)Calculate the molar concentration of 1.00ppm solutions each of Li+ and Pb2+
    (b)What weight of Pb(N

leepbcc   298   1 Reply

jtwalls

Can TEM be used for ultrastructural autoradiography?

Can TEM be used for ultrastructural autoradiography?

Does transmission electron microscopy have the capability to resolve deuterated or tritiated ultrastructure in cells or tissue? I would like to design a pulse chase experiment using radiolabeled phosphatidylcholine in tissue explants.

Juan Ma   271   1 Reply

Leendr

can we cmpare the data of number of cells from membrane filtration technique and serial dilution?

can we cmpare the data of number of cells from membrane filtration technique and serial dilution?

I have to study the impact of temperature on bacteria. So I cultured Vibrio cholerae in a broth. I calculated the number of bacteria in broth by using serial dilution technique. After that, I transferred 1ml of the bacteria from broth into sterile se

darksith77   345   1 Reply

Rima5879

Can you explain to me how to do a problem involving preparing solutions?

Can you explain to me how to do a problem involving preparing solutions?

The question is: What mass (in kg) of Fe(NO3)3 is needed to make 46.9 L of a 2.94 M solution of Fe(NO3)3?

datexy   674   3 Replies

datasian

Can you help me identify this mystery slide?

Can you help me identify this mystery slide?

The picture I have attached is a cell phone pic of a random bacteria slide I looked at in my 200's level micro class yesterday. It was the first day, so I don't really have the expertise to say what it is, but I am really curious. Our profe

dropkickkid   1340   5 Replies

bio_man

Can you include errors in a formal lab report introductions?

Can you include errors in a formal lab report introductions?

I have a lot of detailed info about the lab.  In the conclusion of the intro is it ok to say a few errors?

nursing59   509   1 Reply

ilovebeaches

Can you proofread my paper?

Can you proofread my paper?

For grammatical error or if it doesn't make sense, contirdict myself or confusing, etc?
Thanks

gamingwings   1914   5 Replies

bio_man

Cat sweet unconscious

Cat sweet unconscious

Previous studies through research, scientists discovered that AGR2 domestic cats and wild cats are due to the lack of control sweet perceptron gene tasting a carbohydrate. The cats are complete carnivores, from Meng Niao Research Center and Universit

yoxi5236   1792   1 Reply

someguy100

Cell culture

Cell culture

In all of the videos about cell cultures I've seen they always use cell that were already in a medium and transfer them to another medium.

My question is, how do you grow the first cells?

Thx a lot

fiol10   3036   4 Replies

fiol10

Cell Metabolism

Cell Metabolism

Can someone explain the similarities and differences between cellular respiration and photosynthesis. I understand they both involve chemiosmosis but i don't understand how these processes differentiate in establishing a proton gradient. I would

pumpkinbread   1497   1 Reply

bio_man

Cell Transport Mechanisms and Permeability... Exercise 1

Cell Transport Mechanisms and Permeability... Exercise 1

Need help with PhysioEX: Cell Transport Mechanisms and Permeability... Exercise 1

Activity 1 through 5...

Activity 1: Simulating Dialysis (Simple Diffusion) (pp. 2–4)
Activity 2: Simulating Facilitated Diffusion (pp.

biolove   13535   3 Replies

biolove

Cellular respiration and fermentation

Cellular respiration and fermentation

Working on a lab report, about cellular respiration and fermentation and wondering if I got this right.  Insight or corrections appreciated or you can tell me to just start over if I have gone way off base. Thank you for any suggestions!

Only   3680   2 Replies

Only

Cellular respiration lab

Cellular respiration lab

Hi.  I am doing a cellular respiration lab using soybeans - three beakers.  One with presoaked, one with dry beans and one with none.  Which is my control group?  Not the presoaked, correct?!  And, when bromothymol is added t

tlcone72   10390   9 Replies

laura00

CHE 415 Unit Operations Laboratory II 2015 (Experiment2 -prelab report HEATTRANSFER-STEAM TO AIR)

CHE 415 Unit Operations Laboratory II 2015 (Experiment2 -prelab report HEATTRANSFER-STEAM TO AIR)

CHE 415 Unit Operations Laboratory II 2015  (Experiment2 -prelab report HEATTRANSFER-STEAM TO AIR)

cloveb   757   1 Reply

bolbol

Chem lab due tomorrow and i still cant figure out how to do this problem!?

Chem lab due tomorrow and i still cant figure out how to do this problem!?

This will probably turn out to be simple, but i cant get it, here is the problem  A 0.546 g sample of pure H2C2O4?2H2O crystals is dissolved in water and titrated with 22.40 mL of a potassium hydroxide solution.  What is the molarity of the KOH solut

leenamu   413   1 Reply

jtwl

Chemistry expriment error?

Chemistry expriment error?

A student reported the following combination of unknown mixture"X": 25% NH4CL, 30% NaCl, and SiO2. Assuming these calculations are correct, explain the student's error in this experiment...
*****A student reported the following combination of unknown

datexy   395   4 Replies

Tjones5

Chemistry help pleaseeeeee ?

Chemistry help pleaseeeeee ?

deionized water from a wash bottle was added to wash down the wall of the receiving flask during the titration. how does this affect the reported molar concentration of the saturated Na2s2o3 solution thiosulfate solution ?

The bleach is diluted but

Nurs-4   347   2 Replies

zues1000

Chemistry help, please!

Chemistry help, please!

Having a real brain fart on these questions, could anyone please help me out? Thanks a lot!

Ammonia gas decomposes according to the equation: 2NH3(g) → N2(g) + 3H2(g) If 20.0 L of nitrogen is formed at STP, how many liters of hydrogen will

misterrvincen   1454   1 Reply

misterrvincen

Chemistry help: How do you find the concentration of something given the following information?

Chemistry help: How do you find the concentration of something given the following information?

Hi there - for a lab we have to find the concentration of glucose and the concentration of NaOH in a culture tube given the following information

in the culture tube there are:

4 mL of .1M glucose
4 mL of .2 M NaOH
1 mL deionized water
1 mL methyle

rimrod75   251   1 Reply

juan123

chemistry help?,,, doing a lab on polyprotic acids and titration, please help?

chemistry help?,,, doing a lab on polyprotic acids and titration, please help?

Given that 20.00 mL of phosphoric acid solution required 15.50 mL of 0.200M
NaOH for the first equivalent point. What is the molarity of the phosphoric acid?

feven   1397   2 Replies

Leendr

Chemistry lab - acid base titration

Chemistry lab - acid base titration

Did I do it right?



Results: Molarity of Na

Sadah_17   204   1 Reply

kdot14

Chemistry Lab Final...Acid/Base pKa Calculation....Please Help!?

Chemistry Lab Final...Acid/Base pKa Calculation....Please Help!?

My chemistry lab final is asking us to calculate the molecular mass as well as the pKa values of an unknown monoprotic acid.  We ran a total of 4 titration trials which allowed us to complete the following calculations: Mass of Sample, Initial and Fi

ikilledpablo   436   1 Reply

rimrod75

Chemistry lab help

Chemistry lab help

what is the purpose, theory and conclusion of the acid-base titration lab?

Sadah_17   411   1 Reply

bio_man

Chemistry Lab Help Again!!!?

Chemistry Lab Help Again!!!?

My chemistry lab final is asking us to calculate the molecular mass as well as the pKa values of an unknown monoprotic acid. We ran a total of 4 titration trials which allowed us to complete the following calculations: Mass of Sample, Initial and Fin

Ikkou   392   2 Replies

JUAN99

Chemistry lab question, please help?

Chemistry lab question, please help?

A student titrated the assigned unknown with a volume of 1.54 mL of 0.1000M HCl, using 25.00 mL of the unknown.  Would you consider this a relatively good result?  Explain why or why not?   If not explain how one would change the conditions of the ex

Ikkou   422   1 Reply

rinaann

Chemistry lab report help

Chemistry lab report help

Physical & Chemical Properties/Safety Data Sheet (

Sadah_17   349   8 Replies

Sadah_17

Chemistry Lab results - acids and bases?

Chemistry Lab results - acids and bases?

You will be given 7 unknown solutions ? 4 are aqueous and 3 are solids.  Your job is to determine which substance is which.
The seven substances will be one of the following:
Ammonium hydroxide (aq)
Ammonia (aq)
Nitric acid (aq)
Acetic acid (aq)
Pot

julielpn74   573   1 Reply

JulieA

chemistry related: How many grams of manganese is in the flask?

chemistry related: How many grams of manganese is in the flask?

An erlenmeyer flask contains 81.6 g of KMnO4. How many grams of manganese is in the flask?

thanks so much. could you explain it to me also. do you use percent composition thing?

leezysosteezy   296   1 Reply

LeezaR

Classifying Arthropods Lab

Classifying Arthropods Lab

Does anyone have the answers to the Classifying Arthropods virtual lab please?

deeharris   12796   3 Replies

Gbre123

Cloning, sequencing and expression of amino succinic acid synthesis enzymes

Cloning, sequencing and expression of amino succinic acid synthesis enzymes

Fine amino-succinic acid synthase (ASS1) Continuous Catalytic Synthesis of a thiol compound, and the maintenance of normal cell redox state, protecting ce

yoxi5236   1380   N/A

yoxi5236

Codon contains the protein synthesis rate

Codon contains the protein synthesis rate

The University of California researchers found hidden in the BPNT1 genetic code has never been recognized that information.Their findings due to the development of the University of California, called the ribosome mapping ribosome profiling, technolo

yoxi5236   1803   1 Reply

WallaceT

colloid...what is it?

colloid...what is it?

what is a colloid?

this is what is says

A colloid is a stable suspension of fine particles in a liquid.

what do this means?


thanks
xoxo

nevada   1196   1 Reply

bio_man