Question

Calculate the amount of water in grams produced by the combustion of 16 grams of Methane

Answer 1

To solve such questions you must write a balanced reaction first.

CH4 (g)+2O2 (g)————-> CO2 (g) +2H2O (g)

Now according to the reaction 1 mole of CH4 gives 2 moles of H2O

And 16 grams of Methane mean 1 mole (moles=given mass/molecular mass. Molecular mass of methane is 16)

so 1 mole of methane = 16/16 (given mass 16 and molecular mass 16)

since 1 mole of methane is getting used up to form 2 mole of water.

number of moles=given mass/molecular mass ——- eq. 1

molecular mass of water is 18.

2=x/18 ( where x is the mass of water produced , using equation 1)

2*18=36grams

so 36 grams of water will be produced.

Credit:Ajai Krishna (Quora)