Which of the following statements correctly describe the mole fraction of a component in a mixture?
A- A mole fraction is a unitless quantity
B- The mole fraction of a component can range from 0 to 100
C- A mole fraction can be calculated only when there are two components in the mixture
D- mole fraction can be converted to a mole percent by 100
E- In a mixture of gases, the partial pressure of each gas is proportional to its mole fraction,