Which of the following has largest number of atoms? 1. 1g of Au 2. 1g of Na 3. 1g of Li 4. 1g Cl2

Asked by Prachi Panwar | 23rd May, 2013, 07:36: PM

Expert Answer:

1. Molecular weight of Au = 196.96 g/mol 

Thus, 1g /196.96 g/mol = 0.005 mole of Au

1 mole has 6.022 × 1023 atoms (Avogadro's Number) 

Thus, 0.005 mole Au is (0.005 mol x 6.022 × 1023 atoms/mol) = 3.057 x 1021 atoms
 
2. MW of Na = 23 g/mole
 
No of moles of Na =  1/23
 
So, atoms of Na in moles = 0.04 x 6.022 X 1023  = 2.4 x 1022 atoms
 
3. MW of Li = 6.94
 
Moles = 1/ 6.94 moles = 0.144
 
No of atoms = 0.144 x  6.022 X 1023   = 8.6 x 1022 atoms
 
4. MW of Cl2 = 71 g/moles
 
Moles = 1 / 71 = 0.0140
No of molecules of Cl2 = 0.0140 x 6.022 X 1023 = 8.4 x 1021
In 1 molecule of chlorine there are 2 atoms, So,
 
No of atoms  = 2 x 8.4 x 1021 = 16.8 x 1021 = 1.68 x 1022
 
 
So, largest no of atoms are in 1 g Li
 
 

Answered by  | 24th May, 2013, 10:37: AM

Queries asked on Sunday & after 7pm from Monday to Saturday will be answered after 12pm the next working day.