Question

How many millliters of 2.75 M `H_2SO_4(aq)` are needed to react completely with 47.5 g of `BaO_2(s)`?

Answer 1

`102 \ mL`

Explanation:

Write a balanced chemical equation for the reaction between barium peroxide and sulfuric acid.

`BaO_2 + H_2SO_4 -> BaSO_4 + H_2O_2`

Use the stoichiometry of the equation to find the number of moles of sulfuric acid reacted.

`47.5 \ g \ BaO_2xx (1 mol. BaO_2)/(169.33 \ g \ BaO_2)xx (1\ mol. H_2SO_4)/(1\ mol.\ BaO_2)`

`47.5 cancel(\ g \ BaO_2)xx (1 color(red)cancel(\ mol. BaO_2))/(169.33 cancel(\ g \ BaO_2))xx (1\ mol. H_2SO_4)/(1color(red)cancel(\ mol.\ BaO_2))`

`0.281 \ mol.\ H_2SO_4`

Now, use the molarity formula to find the volume of the sulfuric acid used.

`C_M = n/ V`

Where:

`C_M " "` is the molarity of the acid solution expressed in mol/L.

`V " "` is the volume of the acid solution expressed L.

`n" "` is the number of moles.

`V = n / C_M`

`V = ( 0.281 \ mol.)/(2.75 \ mol. L^-1)`

`V = 0.102 \ L`

`V = 102 \ mL`