Chapter 14 Quizes

14.3:  Mole Fraction and Mass Fraction

  1. Calculate the mole fraction of methane in a 10.0L flask containing 0.367 moles of methane, 0.221 moles hydrogen, and 0.782 moles carbon dioxide.

 

 

 

  1. If the mole fraction for nitrogen in a gaseous mixture were 0.565 and the total number of moles present were 2.49 moles, how many moles of nitrogen are present?

 

 

 

  1. Calculate the mass percent if 7.50g CaCl2 were placed in 500mL of water.  The density of water is 1.0g/mL.  

 

 

 

 

  1. If a scientist needed a NaCl solution that had a mass percent of 2.83%, how many grams of NaCl must be added to 1.00 L of water?

 

 

 

 

 

  1. If 0.589g of KCl is added to a solvent, a mass fraction of 0.482 is measured.  How many grams of solvent must be present.