Question

Complete and balance the equations for the following reactions:

a. 2H₂ + O₂ → 2H₂O
b. CH₄ + 2O₂ → CO₂ + 2H₂O
c. 2K + 2H₂O → 2KOH + H₂↑
d. C₆H₁₂O₆ → 2C₂H₅OH + 2CO₂

Answer 1

Chemical equations are balanced when the number of atoms of each element is the same on both the reactant and product sides. The equations provided are all correctly balanced, as they conserve the respective number of atoms for each involved element.

Step-by-step explanation:

To determine if each chemical equation is balanced, we must ensure that the number of atoms of each element on the reactant side is equal to the number on the product side. Starting with the first equation, 2H₂ + O₂ → 2H₂O is already balanced with 4 hydrogen atoms and 2 oxygen atoms on each side. The second equation, CH₄ + 2O₂ → CO₂ + 2H₂O, is also balanced with 1 carbon atom, 4 hydrogen atoms, and 4 oxygen atoms on both sides.

Moving to the next equation, 2K + 2H₂O → 2KOH + H₂↑ is also correctly balanced with 2 potassium, 2 oxygen, and 4 hydrogen atoms being conserved in the reaction. Lastly, the fermentation equation C₆H₁₂O₆ → 2C₂H₅OH + 2CO₂ correctly balances with 6 carbons, 12 hydrogens, and 6 oxygens on each side of the equation.

If we consider the additionally provided equations for analysis, we must perform different checks to confirm their balance. For example, the equation for the combustion of ethylene is represented as C₂H₄(g) + 3O₂(g) → 2CO₂(g) + 2H₂O(l), which balances with 2 carbons, 4 hydrogens, and 6 oxygens on both sides.

Answer 2

A. Each chemical equation provided in the student's question is correctly balanced, meaning there are equal numbers of each type of atom on both sides of the equation.

Step-by-step explanation:

To determine if each chemical equation is balanced, we must ensure that the same number of each type of atom exists on both sides of the equation.

• 2H₂ + O₂ → 2H₂O: This chemical equation is balanced as it has 4 hydrogen atoms and 2 oxygen atoms on both sides.
• CH₄ + 2O₂ → CO₂ + 2H₂O: This equation is also balanced with 1 carbon atom, 4 hydrogen atoms, and 4 oxygen atoms on each side.
• 2K + 2H₂O → 2KOH + H₂↑: This reaction is balanced with 2 potassium atoms, 2 hydrogen atoms, and 2 oxygen atoms on each side.
• C₆H₁₂O₆ → 2C₂H₅OH + 2CO₂: This equation representing the fermentation process is balanced, containing 6 carbon atoms, 12 hydrogen atoms, and 6 oxygen atoms on both sides.

As for the examples provided for reference, all of them are correctly balanced except for a. 2Na(s) + O₂(g) → 2Na₂O(s) which incorrectly shows two sodium atoms on the reactant side but four in the product (the correct balanced equation should be 4Na(s) + O₂(g) → 2Na₂O(s)). All other examples are correctly balanced.