Question

Calculate the no.of moles and molecules in 19.86gm of Pb(NO3)2

Answer 1

Hello Friend !


Molar mass of NaOH = 23+16+1
                                  = 40 u
​Number of moles = given mass/ molar mass
Given mass = 19.86 g
​Number of moles = 19.86/ 40
                            = 0.4965 mol

1 mole = 6.022 x 10 23 molecules
0.4965 mole = 0.4965 x 6.022 x 10 23molecules
                    = 2.99x 1023 molecules

 
Hope this helps !!