What would be the mass, in grams, of 1.505 x 1023 molecules of carbon disulfide?

19g

Explanation:

Given:

  Number of molecules  = 1.505 x 10²³molecules

 Formula of compound  = CS₂

Unknown:

Mass of the compound

Solution:

 A mole of every substance contains 6.02 x 10²³molecules. Using this we can find the number of moles from number of molecules given;

    6.02 x 10²³molecules makes up 1 mole of a substance

     1.505 x 10²³molecules will contain   = 0.25mole of CS₂  

Mass of CS₂  = number of moles x molar mass

 Molar mass of CS₂  = 12 + 2(32) = 76g/mol

 Mass of CS₂  = 0.25 x 76 = 19g