Introductory Courses

How to solve molality problem?

How to solve molality problem?

In a lab additional questions it asks,
Describe how to prepare 250.0 ml of 0.1000 M AgNO3 from pure  solid silver nitrate.

I don't understand how to solve it.  Someone please explain.

Smilez   287   1 Reply

smilingdeep22

Is there a hair test laboratory to see hair contents?

Is there a hair test laboratory to see hair contents?

I am interested in knowing if laboratories are out there to which doctors can send hair samples (hopefully only the hair above the skin) to get results like the quantity of potassium.

A doctor gave such a test many years ago but maybe he did it with

michaelw000   287   1 Reply

ritinkar4all

Titration Lab??

Titration Lab??

i am a junior in chemistry and i love the class but i can never figure the labs out. can you help?

titration! i understand the concept but the questions make no sense. i dont want the work to be done for me i want to understand so i will leave out

juana.masa   287   1 Reply

darkspirt

What is the name of the liquid that slows down living organisms for easier microscopy?

What is the name of the liquid that slows down living organisms for easier microscopy?

I used it in micro class and cell bio. You add a drop to the slide and it slows the protozoans down. What's it called and where can I buy it?

__Aycee   288   1 Reply

rimah

how to determine whether an unknown solution is acids or bases?

how to determine whether an unknown solution is acids or bases?

For example I was given hydrochloric acid and sodium hydroxide solution of approximately 0.2 M concentration.

1.What strategy would I use to test whether the solution is acid or base??

2. What is the concentration of the unknown?

3. Is the unknown

fewtew   289   1 Reply

smiley77

Please tell me the dilution factor of problem discussed ahead. I made a reaction mix of 2.2ml and then took?

Please tell me the dilution factor of problem discussed ahead. I made a reaction mix of 2.2ml and then took?

1ml of same and further added to this 2ml of water.. What will be the dilution factor.

tonyagodsey   290   1 Reply

ff151djg

How to calculate the molarity of diluted solution?

How to calculate the molarity of diluted solution?

Volume of 6.0 M HCl used for dilution
If 8 ml of acid is added to 42ml water for a total of 50 ml, how do I figure the molarity of the diluted acid solution?

zuca   290   1 Reply

leepbcc

why is it necessary to have a serial dilution in an ELISA?

why is it necessary to have a serial dilution in an ELISA?

In ELISA you have to create a serial dilution of the antibody before putting in the wells, why do you have to do that?

Nursing01   291   1 Reply

nursing 2012

When Young's double slit experiment is done with electrons, do they annihilate each other in the dark regions?

When Young's double slit experiment is done with electrons, do they annihilate each other in the dark regions?

Also, I heard that this experiment has been done with bucky ballls, what was going on with them?  It seems like they would be too massive to have their wave functions cancel each other out.
PS

When two photons undergo destructive interference, do th

bugg   291   1 Reply

LenChan64

What are the uses of these laboratory apparatus?

What are the uses of these laboratory apparatus?

I can't seem to find the uses for these in a laboratory:
adapter
centrifuge
glass tubing
triangular file
voltaic cell

thanks so much.

datheman   292   1 Reply

datpiff

Why do we have to have clinical laboratories?

Why do we have to have clinical laboratories?

Purpose of clinical laboratories?
Effect of clinical laboratories on the environment?
What would happen if there are no clinical laboratories?

Thank you!
Ahahaha, knew someone was definitely going to answer that.
No not really an assignment more of

nursemom   294   1 Reply

buddyhal

Does University of Arizona clinical laboratory science degree program?

Does University of Arizona clinical laboratory science degree program?

My boyfriend is going for his second degree in clinical laboratory science and ASU (Arizona state University) is doing budget cuts and that program MIGHT be one of them. We're looking at other colleges to see if they have the same degree, and if so d

juiewolfe5   294   1 Reply

buddyhal

Need help setting up a chem problem please?

Need help setting up a chem problem please?

Formula: Wtr(weight)/MWt(molecular wgt)=5M(molarity)V(volume). I need to find Molarity, and I have all the other variables. I thought I just needed to isolated M. I did the left side division first, then divided that number by the 5*V. My lab partner

smiley13   296   1 Reply

Nurs-4

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

What si teh proper method for making dilutions?

What si teh proper method for making dilutions?

If a 1:1 dilution is an mix of equal parts, what is a 1:2 dilution? I always thought you subtracted the volume of the concentrated part from the final total volume. For instance, to make a 1:20 dilution, take one part of the concentrate and add 19 pa

smmunday   297   1 Reply

rj.lall

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

What is a cool lab experiment that can spell out words?

What is a cool lab experiment that can spell out words?

What is a cool lab experiment that isn't too hard to obtain materials for, that can spell out words? Something that produces a result like the invisible ink or something, but a bit more visual?

lengjacinto   299   1 Reply

onemustfall!

How Do I Work Out The Dilution Factor?

How Do I Work Out The Dilution Factor?

I did an experiment to work out the percentage of the active ingredient in aspirin and it says i need to know the dilution factor.
Firstly i made up a 100cm3 solution.
I took 1cm3 of that solution put it into a 50cm3 volumetric  flask and added disti

Rimfrost   300   1 Reply

Zug

How to change concentration in chemistry?

How to change concentration in chemistry?

I am doing a chemistry lab with different strengths of acids (weak/strong) using Hydrochloric acid and Ethanoic acid. I was wondering how do you change the concentrations? I know that my teacher will give us maybe a solution with 5 molarity of Hydroc

nzp123   301   1 Reply

juan92garcia

How to determine original cell concentration by colony count?

How to determine original cell concentration by colony count?

I have 50 colonies with a dilution factor of 10^-6. 50 uL of this dilution was plated originally and left over night resulting in the 50 colonies.
How do I determine the original cell concentration in units of cells/mL?

I was thinking of using C1V1

rinadtartir   303   1 Reply

smileylady6770

Why is the charging time different for various light sources in a photoelectric experiment?

Why is the charging time different for various light sources in a photoelectric experiment?

I have noticed that during a photo electric experiment using a electronic h/e device, that the charge time(time to reach stopping potential) for yellow light (lower frequency) takes longer than green light (higher frequency). Is this simply due to th

Firedancer51   303   1 Reply

Smoren

The value of Kp at 25C for compound A when partitioned between methanol

The value of Kp at 25C for compound A when partitioned between methanol

The value of Kp at 25C for compound A when partitioned between methanol (solvent 1) and hexane (solvent 2) is 6.035. Starting with a solution of 1754 g of compound A in 1017 mL of methanol, what volume of hexane (in mL) would be required to extract 1

leftyRN14   305   1 Reply

ikilledpablo1

How do you find the purity of an acid?

How do you find the purity of an acid?

Your task today is to determine the purity of an acid sample. You will be assigned a sample of KHP (the
same acid that was used in the standardization of NaOH experiment). The sample is not pure. The
impurities do not react with a base but the acid d

FFaraz   305   1 Reply

rinadtartir

How to identify 8 unknown solutions?

How to identify 8 unknown solutions?

I need to identify 8 unknown solutions.  I have 8 test tubes each containing one of the following:

NH4OH

NH4Cl

H2O

HCl

NaCl

AgNO3

CH3COOH

NaOH

I know how to precipitate AgNO3 and will test for acidity/alkalinity of NaOH and HCl as I will kno

leeleez   306   1 Reply

Rinab123

How to find molarity again after diluting something?

How to find molarity again after diluting something?

So I diluted a 125mM stock substance (fast green fcf). To do the dilution I used 0.20 ml of the stock and 1.80ml of water. The concentration at the end is 125 uM. What exactly is the molarity for this and how do I find it? Please show me the steps, I

jtw0019   306   1 Reply

Nurnin

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 anyone help me in designing an experiment regarding distance between mirrors n phase difference?

Can anyone help me in designing an experiment regarding distance between mirrors n phase difference?

The aim of the experiment is to investigate the distance between mirrors and the phase difference in the beam produced by lasers. It would be really helpful if apparatus needed for the experiment is mentioned. The experiment is to be conducted in a t

rixter119   307   1 Reply

fionacurley

How long should an animal/insect experiment be conducted?

How long should an animal/insect experiment be conducted?

I am doing a cricket experiment and I will just be observing them. I know how to take care of them and what I'm going to need. I just need to know how long I should take care of them and observe. Any help is appreciated.

firecommon   309   1 Reply

riyaghuman

How do you make a dilution using C1V1=C2V2?

How do you make a dilution using C1V1=C2V2?

So, I'm trying to figure out a couple problems.

To make a 1/100 dilution of solution to a final volume of 100 microliters is 1 microliter of solution to 99 microliters of water.
100 microliters of a 1/10 dilution is 10 microliters solution to 90 mic

TonyaJ98   309   1 Reply

Rima5879

What experiment can i do testing popcorn popping in different microwave levels?

What experiment can i do testing popcorn popping in different microwave levels?

Like for one i can pop it on low, the other on medium, and the last on high.
is there an experiment like that i can do?

rizabove   310   2 Replies

lengjacinto

How do you come up with a dilution scheme?

How do you come up with a dilution scheme?

I dont understand how you come up with calculations to do dilutions. The problem i'm given is that the stock solution of bromothymol blue is 15 ppm. It says to set up a  dilution scheme and use it to produce samples of different concentrations (0, 1,

nursing111   310   2 Replies

rizzy81

What do I need to know involving Forensic Pathology?

What do I need to know involving Forensic Pathology?

Hello, I am a High School student and am extremely interested in Forensic Pathology. I wish to pursue it as a career and was wondering if anyone knew any information at all about this job. Something along the lines of examples of how they became a Fo

ilaeoc   310   1 Reply

ikilledpablo1

How do atoms get built in Laboratory?

How do atoms get built in Laboratory?

How atom are created in Physics laboratory. Are they built by constituents (nucleus--proton, neutron then electrons) or are they separated from a pool of atoms. I read w.wikipedia.org on proton and all they told me that there are plenty of proton in

michaii   310   1 Reply

nursemama0729

Converting microliter of sodium bicarbonate to moles?

Converting microliter of sodium bicarbonate to moles?

Hey there! I'm doing an organic 2 lab & I have to convert 600microliters of sodium bicarbonate (MW=84.007 g/mol) to moles. I seem to have forgotten how to do this, please help!

rinadtartir   310   2 Replies

nurnur

What would happen if the ratio of reactants in a chemical reaction is changed?

What would happen if the ratio of reactants in a chemical reaction is changed?

If I added 10 mL of substance A with 10 mL of substance B, I get 20 mL of substance C. What would happen if I added 20 mL of substance A instead? Any help would be appreciated.

Leen   310   2 Replies

rimazx

Help! Please explain in clear simple words what does my chemistry instructor means by this sentence?

Help! Please explain in clear simple words what does my chemistry instructor means by this sentence?

She has told us to: Transfer the solution quantitatively to an Erlenmeyer flask.
WHAT DOES IT MEAN TO TRANSFER IS QUANTITATIVELY?

ldeeley   311   1 Reply

smirza7198

Compare the inside of the diameters of the 4 measuring instruments and then make a generalization re

Compare the inside of the diameters of the 4 measuring instruments and then make a generalization re

We did a lab on measuring liquids using a graduated  cylinder, beaker, pipette, and burette.
I just dont understand these questions:

Even if the volume of water could be measured very accurately, there would be uncertainty in the mass of the water

tonya1807   311   1 Reply

smiley14

Moles of salt needed for solution of copper?

Moles of salt needed for solution of copper?

Suppose you wanted to prepare 25 mL of a 1.5 M solution of copper (II) sulfate pentahydrate. How many moles of the salt are needed? How many grams is this? Show your work.

This is a lab question.

Nurs-4   312   1 Reply

juan123

How do I explain the concept of an atom to someone in the 16th century?

How do I explain the concept of an atom to someone in the 16th century?

I need to write a two page essay describing the composition, purpose, and looks of an atom to an average 1500's citizen. Needs to be simple enough for them to understand, and perhaps involve some of the scientific beliefs regarding elements at that t

rina08   312   3 Replies

smileyprincess111

How to determine the Molarity of HCl?

How to determine the Molarity of HCl?

This has to do with Titrations.

There were 2 titrations done.

The first one used 18.99 mL of HCl and the second one used 19.01 mL.

There was a molarity of .2 of NaOH solution that was used in both titrations.

How would I find the molarity of the

FF/EMT   313   1 Reply

juan123