When 10.0 grams of CH4 reacts completely with 40.0 grams of O2 such that there are no reactants left over, 27.5 grams of carbon dioxide are formed. How many grams of water are formed? CH4+ 2O2 → CO2 + 2H2O

Respuesta :

znk

Answer:

[tex]\boxed{\text{27.4 g CO$_{2}$; 22.5 g H$_{2}$O}}}[/tex]

Explanation:

We know we will need an equation with masses and molar masses, so let’s gather all the information in one place.  

M_r:      16.04    32.00  44.01   18.02

             CH₄  +  2O₂  →  CO₂ + 2H₂O

m/g:      10.0      40.0

1. Moles of CHâ‚„

[tex]\text{Moles of CH}_{4} = \text{10.0 g CH}_{4} \times \dfrac{\text{1 mol CH}_{4}}{\text{16.04 g CH}_{4}} = \text{0.6234 mol CH}_{4}[/tex]

2. Mass of COâ‚‚

(i) Calculate the moles of COâ‚‚

The molar ratio is (1 mol COâ‚‚ /1 mol CHâ‚„)

[tex]\text{Moles of CO$_{2}$} = \text{0.6234 mol CH$_4$} \times \dfrac{\text{1 mol CO$_{2}$}} {\text{1 mol CH$_{4}$}} = \text{0.6234 mol CO$_{2}$}[/tex]

(ii) Calculate the mass of COâ‚‚

[tex]\text{Mass of CO$_{2}$} = \text{0.6234 mol CO$_{2}$} \times \dfrac{\text{44.01 g CO$_{2}$}}{\text{1 mol CO$_{2}$}} = \textbf{27.4 g CO$_{2}$}\\\\\text{The mass of carbon dioxide formed is } \boxed{\textbf{27.4 g CO$_{2}$}}[/tex]

3. Mass of Hâ‚‚O

(i) Calculate the moles of Hâ‚‚O

The molar ratio is (2 mol Hâ‚‚O /1 mol CHâ‚„)

[tex]\text{Moles of H$_{2}$O}= \text{0.6234 mol CH}_{4} \times \dfrac{\text{2 mol H$_{2}$O}}{\text{1 mol CH$_{4}$}} = \text{1.247 mol H$_{2}$O}[/tex]

(ii) Calculate the mass of Hâ‚‚O

[tex]\text{Mass of H$_{2}$O} = \text{1.247 mol H$_{2}$O } \times \dfrac{\text{18.02 g H$_{2}$O}}{\text{1 mol H$_{2}$O}} = \textbf{22.5 g H$_{2}$O}\\\\\text{The mass of water formed is } \boxed{\textbf{22.5 g H$_{2}$O}}[/tex]