Which of the following equations is not balanced?
[tex]2 Al +6 HCl \rightarrow 2 AlCl _3+3 H _2[/tex]
[tex]2 Na +2 H _2 O \rightarrow 2 NaOH + H _2[/tex]
[tex]SO _2+ O _2 \rightarrow SO _3[/tex]
[tex]C _3 H _8+5 O _2 \rightarrow 3 CO _2+4 H _2 O[/tex]
[tex]2 H _2+ O _2 \rightarrow 2 H _2 O[/tex]
Answer (1)
Analyze each chemical equation by counting the number of atoms of each element on both sides.
Identify that in the equation S O 2 + O 2 → S O 3 , the number of oxygen atoms is not equal on both sides (4 on the reactant side and 3 on the product side).
Conclude that the equation S O 2 + O 2 → S O 3 is not balanced.
The unbalanced equation is S O 2 + O 2 → S O 3 .
Explanation
Understanding the Problem We need to identify the unbalanced chemical equation from the given list. A balanced chemical equation has the same number of atoms of each element on both sides of the equation. We will analyze each equation to check if it is balanced.
Analyzing Equation 1 Equation 1: 2 A l + 6 H Cl → 2 A lC l 3 + 3 H 2 Reactant side: 2 Al, 6 H, 6 Cl Product side: 2 Al, 6 Cl, 6 H This equation is balanced.
Analyzing Equation 2 Equation 2: 2 N a + 2 H 2 O → 2 N a O H + H 2 Reactant side: 2 Na, 4 H, 2 O Product side: 2 Na, 2 O, 4 H This equation is balanced.
Analyzing Equation 3 Equation 3: S O 2 + O 2 → S O 3 Reactant side: 1 S, 4 O Product side: 1 S, 3 O This equation is not balanced.
Analyzing Equation 4 Equation 4: C 3 H 8 + 5 O 2 → 3 C O 2 + 4 H 2 O Reactant side: 3 C, 8 H, 10 O Product side: 3 C, 8 H, 10 O This equation is balanced.
Analyzing Equation 5 Equation 5: 2 H 2 + O 2 → 2 H 2 O Reactant side: 4 H, 2 O Product side: 4 H, 2 O This equation is balanced.
Final Answer The unbalanced equation is S O 2 + O 2 → S O 3 because the number of oxygen atoms is not the same on both sides.
Examples
Balancing chemical equations is essential in various fields, such as environmental science, to understand and control chemical reactions that affect air and water quality. For example, in designing catalytic converters for cars, engineers need to balance equations to ensure that pollutants like carbon monoxide (CO) and nitrogen oxides (NOx) are converted into less harmful substances like carbon dioxide (CO2) and nitrogen (N2) efficiently. By balancing the equation, they can determine the correct amount of catalysts needed to achieve the desired conversion rates, reducing air pollution and improving public health.
