Cell theory states that all the living organisms are made up of basic structural and functional units, cells. All cells divide and give rise to new cells. All the cells have similar chemical composition. The nuclei acid DNA present in the chromosomes helps in carrying hereditary information from generation to generation. So, in order to sustain life the cells must contain DNA either enclosed in the nucleus or freely floating in the cytoplasm.
First you need to find the mass of one mole of the element. (say Fe)
Find Fe on the periodic table, it should tell you what the average atomic mass is.
The average atomic mass = mass of one mole.(in this case it is 55.85g)
Take your moles (1.35mol Fe) and multiply it by the mass of one mole (55.85g)
1.35mol*55.85g/mol=75.39g
(Just repeat that method for the other problems) use the formula <span><span>moles=<span><span>mass</span><span>Molar mass
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