Question

How many moles of CO2 will be produced from 97.0 g of C3 Hy, assuming O2 is available in excess?

Answer 1

Answer:

• 291 / (36 + y)

Explanation:

Regardless of the value of the y subscript, the number of moles of CO₂ that can be produced from 1 mol of  $C_3H_y$ is 3 moles: that is so because every molecule of   $C_3H_y$ contains 3 atoms of C and every atom of C produces one molecule of  CO₂.

Then, you can calculate the number of moles of  $C_3H_y$ in 97.0g using the molar mass of the compound:

1. Molar mass of    $C_3H_y$ :

• 3 × 12g/mol + y × 1 g/mol = (36 + y)g/mol

2. Number of moles = mass in grams / molar mass

• Number of moles of    $C_3H_y$  =

                                           =   97.0 g / (36 + y)g/mol = 97.0/(36+y) mol

3. Number of moles of CO₂

As stated above, the number of moles of CO₂  is 3 times the number of moles of    $C_3H_y$ :

• Number of moles of CO₂ = 3 × 97.0 / (36 + y) mol = 291 / (36 + y)

For instance, imagine the compound is C₃H₈. How many moles of CO₂ will be produced from 97.0 g of C₃H₈?

You can replace 8 for y:

• 291 / (36 + 8) mol = 291.0 / (44) mol = 6.61 mol