Question

What is the total number of atoms contained in 2.00 moles of nickel?

Answer 1

  The number of  atoms  that are contained in  2.00 moles  nickel  is calculated  by use of Avogadro  law  constant

that is  1 mole  =  6.02  x10^23   atoms

what  about 2 moles = ?  atoms

= ( 2moles /1mole)  x 6.02 x10^23  atoms = 1.204  x10^24  atoms   of nickel  are there in  2 moles  of nickel

Answer 2

Avagadros number states that 1 mol of any substance is made of 6.022 x 10²³ units. These units could be atoms making up elements or molecules making up compounds.
1 mol of Nickel (Ni) is made of  6.022 x 10²³ atoms of Ni
therefore 2.00 mol of Ni is made of  6.022 x 10²³ x 2.00 = 1.20 x 10²⁴ atoms of Ni
therefore 2.00 mol of Ni is made of 1.20 x 10²⁴ atoms of Ni