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10 Nov 2019

So Im working on a problem where I need to calculate some ttests. The problem gives me this equation.....

With all my work and the data the problems gives me Ihave

X=.41664

u=.42100Â±.00004

s=.00457

n=11

I'm trying to solve for t and I just cant figure out how tosub and divide numbers that have uncertainties with numbers thatdont....CAN SOMEONE HELP!?!

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Hubert KochLv2

17 May 2019

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and n = number of moles

Does my equation look correct?

I calculated n using the mass of the Mg sample and dividing it by the molar mass of Mg

What do I use as the mass for the experiment?

Do I use the mass of the Mg sample?

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Or is it the total mass of the stuff in the calorimeter, so the mass of the Mg sample and the mass of the 100mL of 1.0M HCl?

Help would be appreciated, I've been working on this for 20 hours, most of it trying to figure out what to do, I did try talking to our lab professor but he didn't want to help me.

I'm working on a project I need some help with (BTW I asked my teacher and I am allowed to ask for help). If there was anything I wasn't clear on please tell me because I'm just hopelessly lost on this. Also just to note this actually has a fair bit of chemistry in it but because it's all related to electricity and there is no chemistal engineering subject Tab I put it here.

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Good Afternoon,

I am doing a laboratory report for the course entitled: Principles of Instrumental Analysis. It is a 4th year course and i have been tasked with the following analytical problem, "Determine the DEET composition in common bug sprays." In other words, I have to determine the concentration of DEET in a couple of bug sprays. The sprays and DEET are supplied. Secondly, I have to prepare a protocol for measuring the concentration of DEET in my samples and a GC:MS method for analysis of DEET. By the way, GC:MS is short for 'Gas chromatographyâmass spectrometry' and as you may know it is an analytical method that combines the features of gas-chromatography and mass spectrometry to identify different substances within a test sample. Basically, I need your help in giving me a layed-out protocol (such as we would see in a manual) of what I will do in the lab to answer the above analytical problem. You can think of it as a lab manual that you would write so that someone else could go in the lab and perform the experiment in your place.

It should have all of these components.

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I'm not quite understanding. Thank you for your clarification once again.

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