Answer:
The mass of O₂ that will be needed to burn 36.1 g B₂H₆ is 125.29 g.
The atoms of the reactant rearrange to form new products.
It is the electron sharing.
electronegative element + electronegative element
exemple :
O₂ , H₂
hope this helps!
Answer: The molar mass of each gas
Explanation:
Mole fraction is the ratio of moles of that component to the total moles of solution. Moles of solute is the ratio of given mass to the molar mass.

Suppose if there are three gases A, B and C.
a) 
b) 
c) 
moles of solute =
Thus if mass of each gas is known , we must know the molar mass of each gas to know the moles of each gas.