Question

Calculate the mass of water produced when 4.22 g of butane reacts with excess oxygen. Express your answer to three significant figures and include the appropriate units.

Answer 1

first calculate the no o fmoles of Butane

no of moles of Butane = weight of butane / molar mass of butane

= 4.22 g / 58.124 g /mol

= 0.0726 moles

write the bvalanced equation

2C₄H₁₀ + 13O₂ ------> 8CO₂ + 10H₂O

from this equation from two mole mole of butane 10 mole of H2O is froming

that means from one mole of butane 5 moles of H2O

from 0.0726 moles of butane 5 x 0.0726 moles = 0.363 moles of water will produce

mass of the water = moles of water x molar mass of water

= 0.363 moles x 18 g/mol

= 6.534 g of H2O will produce