Question

Acetylene (CH) gas is often used in welding torches because of the very high heat produced when it reacts with oxygen (0) gas, producing carbon dioxide gas and water vapor. Calculate the moles of acetylene needed to produce 0.055 mol of carbon dioxide. Be sure your answer has a unit symbol if necessary, and round it to 2 significant digits.

Answer 1

1)

balanced equation :

2 C2H2 (g) + 5 O2 (g)   --------> 4 CO2 (g) + 2 H2O (g)

2 mol acetylene --------> 4 mol CO2

   ?? C2H2    ------------> 0.055 mol Co2

moles of acetylene = 0.055 x 2 / 4

                              = 0.0275 mol

moles of acetylene = 0.028 mol

2)

6 CO2 (g) + 6 H2O (l)   --------------> C6H12O6 (s) + 6 O2 (g)

1 mol glucose ---------> 6 mol CO2

1.6 mol glucose ------> ??

moles of CO2 needed = 1.6 x 6

moles of CO2 = 9.6 mol