I have been working all day trying to do a proper graph for my lab report and somehow find the concentration of the unknown based on the curve. I'm literally saved now, THANKS A LOT!
Thank you Mark for this very helpful tut. Don't know Excel but you saved me today when I needed to generate a curve and plot absorbance unknowns. Great job and again thank you very much.
Haha. Thank you for the kind words. No sign of any $20s, but knowing that my former students and other kind souls on the Internet are better prepared because of the video is all the thanks that I need.
How do you know what values to use for the standard curve? The lab we did involved NaOH and Crystal Violet, all i have are absorbance values and I need the concentration decrease.
Great video, but I had to make a serial dilution of my unknown sample too, however I only need to find the conc. of the NEAT sample. Is there any point to do a serial dilution of the unknown? My prof also wants error bars on the standard curve since we made the serial dilution in a triplicate but I think i can figure this out for myself. Again really appreciate the insight.
Hi this was so much help thank you! I don't know wether you could tell me how to then add the new found unknown values onto the graph created in the first place?
hello..thanx for the helpp..i had a question how do i plot that unknown concentration on the same graph...for example to mark that unknown concentration corresponding to absorbance and draw line showing it on the graph...your help will be appreciated..i hope i made myself clear
hi mark. when you use the equation that you have shown in the tutorial to calculate the concentration of the unknown, the result is different though slightly than what you have got after entering value in the specified cell... i tried with bigger numbers and there the difference is more..which is the correct one and which one should be used? Pl help
Thank you so much! This video helped me alot. I wanted to ask though, whether a semi-logarithmic standard curve will give us correct values using this same formula?
Either use a mouse with two buttons, or hold control as you click. You can also set your trackpad to recognize when you have two fingers on it, and it will treat that as a right click.
I actually do have one for Apple Numbers (09), which will behave similarly to the updated Numbers: Determining the Concentration of an Unknown Sample Using the Standard Curve Numbers '09, however, if you would like, I can also make a tutorial for that version as well!
In numbers, the function should be =forecast, not =trend. I go over some of the caveats of using forecast in numbers in that video that I posted for you in my previous content (it is near the end). The absorbance line should always be linear if you are creating a line of best fit based off of your data (trendline) because absorbance and concentration are linearly related.
The independent variable is the variable that the researcher manipulates. In this particular instance, the concentration is what the researcher changes, and, as a result, it is on the x-axis. The absorbance changes in response to the change in concentration, and is therefore the dependent variable.
I'm sorry about that. When I made these videos I was having to make sure that everyone was starting from same initial point (even if they already understood some of the basics). In future videos, I will try and provide a list of steps in writing to better cater to everyone!
This video was God sent. I was losing my mind trying to figure out how to do this and my lab report is due tomorrow. Thank you so much
I have been working all day trying to do a proper graph for my lab report and somehow find the concentration of the unknown based on the curve. I'm literally saved now, THANKS A LOT!
Thank you Mark for this very helpful tut. Don't know Excel but you saved me today when I needed to generate a curve and plot absorbance unknowns. Great job and again thank you very much.
Thank you. Even working on Excel 2013, I could still understand and follow everything. Very helpful.
Thank you so much, this has just saved me for my forensic science degree portfolio. Without this I would have been completely lost. Best wishes x
This is an excellent video and the narration, pace and quality helped me tremendously with my Chem Lab report. Thank you!
thanks a lot man! i was so confused on how to do this for my chemical engineering report and then i found this video. It really helped me a lot.
Thank you so much for posting this video. Helped me tremendously in biochemistry.
This is so so helpful, thank you so much!!!! you have no idea how you've made my day.
Thank you so much for this simple explanation, I couldn't find it anywhere on the web.
Thanks! I didn't realize you needed to take the opposite values for x and y on your standard to make the unknown work. Very helpful!
A big thanks from Korea, Mark ^^
You are very welcome! So glad that you found it helpful!
I come back to this for every single lab report
Shh, don't tell anyone...
Thank you very much!
Thank you Mark, really appreciate this.
I know everyone is saying this but oh my gosh this video was so wonderfully helpful! I hope you find $20 on the ground or something special like that
Haha. Thank you for the kind words. No sign of any $20s, but knowing that my former students and other kind souls on the Internet are better prepared because of the video is all the thanks that I need.
Thanks man, I was stuck in this same problem for whole day!!
Finally a good education video about determining unknown concentracion! THy very much
Please tell that should the absorbance of standard be always less than 1 ?
This is a fantastic video; extremely thorough and useful! Thank you so much for posting it!
Can anyone help me with the manual calculation when used graph paper
Thank you so much you have opened my brain and eyes. very brain storming lecture
at 06:36 how did you get the figures automatically beside the trend ?
I just want to say thank you very much for this video! Its a life saver
What the concentration did you find here ? concentration of feed or permeat ?
even though this was posted 5 years ago it helped me do my biochem lab write up thank you !!!!!!
Fantastic news! You are very welcome!
Fantastic and clear explanation thank you so much keep it up...:-)
What Lacie said, how do you get the unknowns plotted on the existing graph? I tried adding data with a source 2
how do i plot the line showing how i found the concentration using standard curve????
Very helpful and I have a windows! How would you plot those points on your trendline? add another series?
You saved me with that trend! Thanks
Perfectly clear and so helpful. Thank you!
Really helpful. The link to your office however does not work.
Prabodh Kumar yeah, sorry about that, I changed the links on my website. I will update it so that there is a redirect to the new page.
if you add 0.2 absorbance for the unknown, the concentration does not show 5 as per the standard curve. Is this the right formula?
How do you know what values to use for the standard curve? The lab we did involved NaOH and Crystal Violet, all i have are absorbance values and I need the concentration decrease.
Great video, but I had to make a serial dilution of my unknown sample too, however I only need to find the conc. of the NEAT sample. Is there any point to do a serial dilution of the unknown? My prof also wants error bars on the standard curve since we made the serial dilution in a triplicate but I think i can figure this out for myself. Again really appreciate the insight.
Thank you so much, this video saved my life
This was incredibly helpful. Thank you very much!
Hi this was so much help thank you! I don't know wether you could tell me how to then add the new found unknown values onto the graph created in the first place?
Thanks, It was helpful for me !
You are very welcome!
how can you get the unknown concentration to be a point on the curve?
THANKS ITS HELPFULL
BUT IF I HAVE MORE THAN ONE SAMPLE OR I NEED TO CALCULATE MORE SAMPLE AT ONCE HOW CAN I DO IT
THANKS AGAIN
Excellent explanation. thank very much.very useful.
hello..thanx for the helpp..i had a question how do i plot that unknown concentration on the same graph...for example to mark that unknown concentration corresponding to absorbance and draw line showing it on the graph...your help will be appreciated..i hope i made myself clear
Hi Mark. How do you calculate the protein content in percentage , given the protein concentration obtained?
HI MR.MARK
CAN YOU TO SEND IN MY E MAIL ORGINAL REPORT IN EXEL.I TRY TO FIND MORE TIMES BUT SOMTHING IS WRONG.
THNX
Hey #trend I lOOOve yoU:)... u don't know how much u helped me today THANK U SO MUCH...NEVER FORGET THIS
Somi A I'm happy I could help!
Known absorbance is being used to calculate unknown concentration
Thanks, great video and very simple..:)
You are welcome! Glad I could help!
Thanks a lot
Could you please explain how to optain more than on unknown sample for example 100 in sample with the same way in schedule
Thanks again
hi mark. when you use the equation that you have shown in the tutorial to calculate the concentration of the unknown, the result is different though slightly than what you have got after entering value in the specified cell... i tried with bigger numbers and there the difference is more..which is the correct one and which one should be used? Pl help
Thanks a lot for your help!
I freakin love you! you are a life saver, thank you sir!!!
Happy to help!
do we have to set the intercept of the trend-line to 0.0?? isn't it necessary ?
really appreciate the help!
purplesoren Happy it helped!
really, fantastic teaching wonderful presentation, simply talk, thanks
Really helpful, thanks!
Thank you! Lol you taught me how to use excel on mac xD
ivy ling You are welcome! Happy to help!
THANK YOU MR!
thank you..!! you saved me.
Thanks!! Very clear!
Hi Mark,
Thank you for this awesome video. I have a quick question when I used the 0.13 absorbance I did not get the 2.5 concentration. Thanks
Thank you so much! This video helped me alot. I wanted to ask though, whether a semi-logarithmic standard curve will give us correct values using this same formula?
How do you right click on a MAC??
Either use a mouse with two buttons, or hold control as you click. You can also set your trackpad to recognize when you have two fingers on it, and it will treat that as a right click.
omg.. thank you very much!
Lifesaver! Thank you so much!
You are welcome! I am happy that it helped!
Thank you so much!
You are very welcome!
i appreciate this so much.. thank you =)
Thank you very much, helped me a lotttt!!!!! :)
If you could prepare one similar tutorial for Apple numbers, I think it would be great!
I actually do have one for Apple Numbers (09), which will behave similarly to the updated Numbers: Determining the Concentration of an Unknown Sample Using the Standard Curve Numbers '09, however, if you would like, I can also make a tutorial for that version as well!
In numbers, the function should be =forecast, not =trend. I go over some of the caveats of using forecast in numbers in that video that I posted for you in my previous content (it is near the end). The absorbance line should always be linear if you are creating a line of best fit based off of your data (trendline) because absorbance and concentration are linearly related.
Thank you very much.
Great .Thanks a lot
Thank You mark!
You are very welcome!
It's absorbance vs concentration. Absorbance is the independent variable
The independent variable is the variable that the researcher manipulates. In this particular instance, the concentration is what the researcher changes, and, as a result, it is on the x-axis. The absorbance changes in response to the change in concentration, and is therefore the dependent variable.
Some one please tell me how to do this with Dcpip and vitamin C
thanks
You are welcome!
Did you ever find this out?
doesnt work just shows up empty
u saved my ass mark , thanks a lot
You are quite welcome!
thnxxxx
You are quite welcome!
so dumb. I have to watch a 10 min video to solve 1 stupid problem. Thank you though.
I'm sorry about that. When I made these videos I was having to make sure that everyone was starting from same initial point (even if they already understood some of the basics). In future videos, I will try and provide a list of steps in writing to better cater to everyone!
GET TO THE DAMN POINT A LOT EARLIER IN THE CLIP
thank you for WASTING ten minutes of my life which I will never get back. I am stuck and helpless. What is the meaning of life
how do I plot the unknown concentration that I got into the standard curve graph?
Thanks dude, big help
Thank u very much!
Nabilah Baby You are very welcome!
Nabilah Baby You are very welcome!
Thank you so much!
You're welcome!