Question

You have 16.7 grams of hydrogen and 15.4 grams of oxygen in a synthesis rxn. Which is the limiting reagent?

Answer 1

Oxygen is the limiting reagent in the following synthesis reaction.

Step-by-step explanation:

At first, we have to balance the chemical reaction,

`2H_(2)+O_(2)`
`2H_(2)O`

i.e.,oxygen molecule requires 2 moles of hydrogen molecule in order to synthesise 2 moles of water molecule.

no. of moles of
`O_(2)` =
`(15.4*1)/(32)`

=0.48125 moles

no. of moles of
`H_(2)` =
`(16.7*1)/(2.0159)`

= 8.2841 moles.

Now, for 1 mole of oxygen,2 mole of hydrogen is used, so;

no. of moles of
`H_(2)` = 8.2841/2 = 4.142 moles.

But, we don't have that many moles of
`O_(2)` and that's why, oxygen is considered as limiting reagent.