Question

help with parts A-D please

Exercise 6.38 Calculate the mass in grams of each elemental sample:

Answer 1

part-A

1 mole of uranium = 6.023*10^23 atoms

6.023*10^23 atom = 1 mole of uranium

6.023*10^23 atom   = 238g of uranium

1.33*10^20 atom = 238*1.33*10^20/(6.023*10^23)   = 0.0526g of uranium

part-B

6.023*10^23 atom   = 65.4g of Zn

2.6*10^22 atom   = 65.4*2.6*10^22/(6.023*10^23)    2.823g of Zn

part-C

6.023*10^23 atoms = 1 mole of Pb

6.023*10^23 atoms = 208g of Pb

5*10^23 atoms     = 208*5*10^23/(6.023*10^23)   = 172.67g of Pb

part-D

6.023*10^23 atom = 1 mole of Si

6.023*10^23 atom = 28g of Si

6.53*10^24 atoms = 28*6.53*10^24/(6.023*10^23)   = 304g of Pb