mole conversions

1. A)conversions from paricles---mole
 Ex:  3.01 x 10^24----particles/moles
         3.01 x 10^24particles  x  1mole/6.022 x 10^23particels =5.00moles

    B)moles---particles
        0.75moles CO2---molecules
        0.75moles x 6.022 x 10^23molecules/1mol = 4.5 x 10^23molecules of CO2

     C)0.75moles CO2---atom of oxygen
         4.5 x 10^23molecules CO2  x  2atoms/1molecules CO2 = 9.0 x 10^23 atoms of oxygen

2.A) conversions from moles----grams
         2.04moles C---grams
         molar mass of C---12g/mole
          2.04moles x 12g/mole = 24.5g of C

    B)grams---moles
       3.45g C ---moles
       3.45g x 1mole/12.0g = 0.288moles

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3 A) particles --mass

        2.78 x 10^22 Fe atoms    x   1mole/6.022 x 10^23    x  55.8g/1mole  = 2.58 g

    B)mass- particles

        20.0g Fe  x 1mole/55.8g  x 6.022 x 10^23particles/1mole = 2.16 x 10^23particle

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