Which of the following does NOT contain the same number of atoms as 3.30 moles of K?
A) 3.30 moles of K
B) 1.50 moles of Hf
C) 3.30 moles of Os
D) 3.30 moles of Co
E) 3.30 moles of Au

Question

Quizplus · Accepted Answer

To find the number of atoms in any given amount of substance, we need to use Avogadro's number (6.022 x 10^23 atoms/mol). Therefore, 3.30 moles of K will have:
(3.30 mol K) x (6.022 x 10^23 atoms/mol) = 1.986 x 10^24 atoms of K

Using the same formula for the other options, we can see that:
A) 3.30 moles of K will have 1.986 x 10^24 atoms of K (same as the calculation above)
B) 1.50 moles of Hf will have (1.50 mol) x (6.022 x 10^23 atoms/mol) = 9.033 x 10^23 atoms of Hf (not the same as the calculation for K)
C) 3.30 moles of Os will have (3.30 mol) x (6.022 x 10^23 atoms/mol) = 1.986 x 10^24 atoms of Os (same as K)
D) 3.30 moles of Co will have (3.30 mol) x (6.022 x 10^23 atoms/mol) = 1.986 x 10^24 atoms of Co (same as K)
E) 3.30 moles of Au will have (3.30 mol) x (6.022 x 10^23 atoms/mol) = 1.986 x 10^24 atoms of Au (same as K)

Therefore, option B (1.50 moles of Hf) does NOT contain the same number of atoms as 3.30 moles of K.

Which of the Following Does NOT Contain the Same Number