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AS Chemistry help

Hi, can someone help me with this question
A student heats 3.25 g of a hydrated Group 1 carbonate in a crucible, until all the water has evaporated;
M2CO3•10H2O M2CO3 + 10H20
After heating, 1.20 g of the anhydrous Group 1 carbonate forms.
Calculate the relative formula mass of the anhydrous Group 1 carbonate and hence, identify the Group 1 metal M
1. Find number of moles of hydrated Metal Carbonate using n=mass/mr and sub in X for mr of the metal. E.g 3.25/(240 2X)=n
2. Since ratio of moles is 1:1, equate to find mr of anhydrous metal carbonate in the 1.2 grams. n=mass/mr so mr=mass/n 60 2X=(1.2)/(3.25/(240 2X))
3. Solve to find X.
(edited 6 years ago)
Original post by AvogadrosAvocado
1. Find number of moles of hydrated Metal Carbonate using n=mass/mr and sub in X for mr of the metal.
2. Since ratio of moles is 1:1, equate to find mr of anhydrous metal carbonate in the 1.2 grams.
3. Solve to find X.

4. Use value of X to identify metal.

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