I need help asap :( Its worth 60 points 20 grams of hydrogen reacted with oxygen to form 36 grams of H20 (water). How many grams of oxygen were used up in this reaction?

Mass of oxygen react = 32 g    

Explanation:

Given data:

Mass of hydrogen = 20 g

Mass of oxygen = ?

Mass of water formed = 36 g

Solution:

Chemical equation:

2H₂ + O₂     →      2H₂O

Number of moles of water formed:

Number of moles = mass/molar mass

Number of moles = 36 g/ 18 g/mol

Number of moles = 2 mol

No we will compare the moles of water with oxygen.

               H₂O          :             O₂

                 2            :              1

when two moles of water formed one mole of oxygen react.

Mass of oxygen react:

Mass = number of moles × molar mass

Mass = 1 mol × 32 g/mol

Mass = 32 g    

the answer is option a.