Molar mass 18 Calculate the molar mass of lead element, knowing that the mass of 0.2 mol
of it equals 41.4 g

207g/mol

Explanation:

Given parameters:

Mass of the lead  = 41.4g

Number of moles  = 0.2mole

Unknown:

Molar mass of lead = ?

Solution:

The molar mass of substance is related to mass and number of moles using the expression below;

           Mass = number of moles x molar mass

        Molar mass =

Now insert the parameters and find the molar mass;

     Molar mass =   = 207g/mol

a saline water is fed to a reverse osmosis unit at flow rate o rotameter connected to reject (retentate) line reads 8 installed in reject and permeate line reads 15.2 milli siemens/cm and 300 micro siemens/com respectively.