chemistry moles

Question

According to the following reaction, how many grams of carbon dioxide will be formed upon the complete reaction of 28.0 grams of water with excess carbon monoxide ?

carbon monoxide(g) + water(l)  carbon dioxide(g) + hydrogen(g)

Answer 1

Firstly write out the equation for this reaction and ensure it is balanced

CO + H₂O ----------> . CO₂ + H₂ which is balanced. Next find the molecular weight of each of the reactants and products (Very important to make sure that the equation is balanced before continuing):

CO = 12 + 16 = 28

H₂O = 1+1+ 16 = 18

CO₂ = 12 + 16 + 16 = 44

H₂ = 1 + 1 = 2

We can now find the number of moles of water in 28 g:

28 g H₂O x 1 mol H₂O/18 g H₂O = 28/18 = 1.56 moles of water are used.

Since from the balanced equation, because 1 mol of H₂O produces 1 mol of CO₂ , then 1.56 moles of water produces 1.56 moles of carbon dioxide:

Therefore the mass of 1.56 moles CO₂ is

1.56 moles CO₂ x 44 g CO₂/1 mol of CO₂ = 68.64 g of CO₂

So the mass of carbon dioxide produced is 68.64g

Answer 2

Write a balanced equation: CO(g) + H₂O(l) ==> CO₂(g) + H₂(g)

Using dimensional analysis, we have...

28.0 g H₂O x 1 mole H₂O/18.0 g x 1 mole CO/mole H₂O x 44.0 g CO₂/mole CO₂ = 68.4 g CO₂