Question

16.26
milligram of sample of an element “X” contains 1.66x1020
atoms. What is the atomic mass of element “X”?

Answer 1

I hope thats not 1020, but $10^{20}$
So, 1.66 x $10^{20}$ atoms weigh 16.26 milligram
1 atom will weigh $\frac{16.26}{1.66* 10^{20} }$ milligram
So, 6.022 x $10^{23}$ atoms weigh $\frac{16.26}{1.66* 10^{20} }$ * 6.022 x $10^{23}$
So, the weight will be 58.986 * 1000 milligrams = 58.986 grams.
Hence the atomic weight of the atom of the Element x is around 59 grams.

Answer 2

Answer:

firstly find mass of 1 atom

then 6.022×10²³ atoms mass (it is equal to the atomic mass)

hope it helps