Question

the number of molecules in 4.25gram of NH3 is

Answer 1

As, molecular mass of NH3 = 14+ 1x 3 = 17

then, no. of moles = 4.25/17                                                                                             =0.25 moles

so, no. of molecules = 0.25 x 6.022 x 10^ 23                                                            =1.5055 x 10^ 23 molecules