Question

1 mole of all substances contains the same number of specified particles.
a) Calculate the number of molecules present in 3.2 g of Oxygen.
b) How many grams of carbon will have the same number of atoms as 4g of Ca

Answer 1

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Answer 2

a) use: \(n=\dfrac{m}{M}\)

where, n=moles, m=mass (in g), and M=molar mass (found on the periodic table).


b) the number of molecules is proportional to the amount of moles. So, find how many moles 4 g of calcium are, then find the amount of grams (mass) of C that is equal to that amount of moles (use the same formula).