How many grams of oxygen are required to produce
9 grams of water at standard conditions?
2 H, + 0, → 2H20
grams

4g

Explanation:

Equation of reaction

2H₂ + O₂ → 2H₂O

Molar mass of O2 = 16g/mol

Molar mass of water = 18g/mol

Number of moles = mass / molar mass

Mass = molar mass × number of moles

Mass of O2 = 1 × 16 = 16g

Mass of H2O = 2 × 18 = 36g

So from equation of reaction,

16g of O2 = 36g of H2O

X of O2 = 9g of H2O

X = (9 × 16) / 36

X = 4g

4g of O2 will produce 9g of H2O

the answer would be b i believe