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# Calculating Relative Atomic Mass from an experiment watch

1. So tomorrow we're meant to be doing PAG 1.2, Determination of the Relative Atomic Mass of Magnesium. I understand the experiment method but I don't know how you're meant to work out the relative atomic mass just from doing an experiment? Help please!
2. You will be given mass of Magnesium. Then you will also be given a solution that you mix the magnesium with.
For example I am given 2.6g of magnesium and I mix it with 50cm3 of 0.2moldm-3 HCl. Work out the relative atomic mass of Magnesium.
Work out moles of HCl 0.05 * 0.2 = 0.01 moles of HCL.
You will need the reaction equation 2HCL + Mg ---> MgCl2 + H2

I need to half the moles because of the 2:1 ratio. 0.01/2 = 0.005 moles
then use Mass/ Moles = relative atomic mass

I made this whole thing up, this is just to give you an idea. The whole experiment can be anything, we did this, but were told to work out the element X by working out relative atomic mass. Just keep an eye open for the quantitative results and use formulas.

Hope I am right and this makes sense. Good luck

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Updated: October 10, 2017
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