he molar mass of gold is 0.197kg. Calculate the mass of a gold atom, to 3 SF. (1 mole = 6x10e23)
Just divide the mass by Avogadro's number (given in the question as 6*1023)
$$\frac{0.197}{6\times 10^{23}}= 0.03283\times 10^{-23}kg$$
or
$$3.28\times 10^{-25}kg$$
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Thanks Alan,
So is there always 6x10^23 atoms in a mole (of anything) ?
Can you (or someone else) tell us a little about the significance of Avogadro's number? (Only if is relatively easy to do. )
By definition a mole is Avogadro's number worth!
Avogadro's number is more precisely given by: 6.02214129×1023
Have a look at http://en.wikipedia.org/wiki/Avogadro_constant for more details.
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