Question

What coefficients must be placed in the following blanks so that all atoms are accounted for in the products?

C₆H₁₂O₆→ _C2H₆O+ _CO₂

a. 2; 1
b. 3; 1
c. 1; 3
d. 2; 2

Answer 1

To balance the chemical equation C6H12O6 → _C2H6O + _CO2, one needs to account for the number of carbon, hydrogen, and oxygen atoms on both sides of the equation. The correct coefficients to balance this equation are 2 molecules of C2H6O (ethanol) and 2 molecules of CO2 for option d (2; 2). These coefficients ensure that each element is present in the same number on both sides of the equation.

Step-by-step explanation:

The student's question asks to identify the correct stoichiometric coefficients for the compounds in the given reaction equation C₆H₁₂O₆ → _C2H₆O + _CO₂. To balance the chemical equation, carbon (C), hydrogen (H), and oxygen (O) atoms on both sides of the equation need to be accounted for. The breakdown would be as follows:

• C6H12O6 contains 6 carbons, 12 hydrogens, and 6 oxygens.
• C2H6O (ethanol) contains 2 carbons and 6 hydrogens.
• CO2 contains 1 carbon and 2 oxygens.

To balance carbons, we note that 3 molecules of C2H6O will provide 6 carbon atoms, matching the reactant side. To balance hydrogens, 3 molecules of C2H6O will also yield 6*3 = 18 hydrogens, which exceeds the 12 hydrogens from C6H12O6. We can get rid of excess hydrogens by producing water (H2O) in the reaction.

In terms of oxygen atoms, we have 6 from C6H12O6 and need to distribute them among ethanol and carbon dioxide. With 3 molecules of ethanol, we have already 3*1 = 3 oxygens. The remaining oxygens will form CO2. So each molecule of CO2 requires 2 oxygens, and with 3 oxygens left, we need 3/2 = 1.5 which translates to 2 CO2 molecules with an added half oxygen from the ethanol side. This gives us the balanced reaction:

C6H12O6 → 2C2H6O + 2CO2

However, this still doesn't account for all atoms because of the introduction of water (H2O) to balance hydrogens:

C6H12O6 + O2 → 2C2H6O + 2CO2 + H2O

To finalize the balancing, we need to tweak the coefficients to satisfy the oxygen balance, which will ultimately yield 2 molecules of ethanol and 2 molecules of CO2, as option d suggests. So the final equation would be:

1C6H12O6 → 2C2H6O + 2CO2