Question

Calculate the no of molecules present in 19g of water

Answer 1

Answer:

number of molecules in 19g of water is 6.35×10²³.

Explanation:

According to the given data,

       mass of water = 19$g$

we know that,

         molecular mass of water = 18$g/mol$

according to the equation:

 number of moles in 19$g$ of water is = $\frac{given mass}{molecular mass}$

                               = $\frac{19}{18}$

                                 = 1.055 $moles$

we know that number of molecules in one mole of substance =          

                                                                                        = 6.022×10²³ molecule

Therefore,  number of molecules of water in 1.055 mole = 1.055 × 6.022×10²³

                                                                             = 6.35×10²³molecules

Therefore 19 g of water contains 6.35×10²³molecules in it.