Select the correct answer.
This chemical equation is not balanced:
[tex]AgBr(s)-Ag(s)+Br_2(g)[/tex]
Why isn't it possible for the reaction to occur as indicated by the unbalanced equation?
A. There are more substances on the right side of the equation than on the left side.
B. There is a gas on the right side of the equation but not on the left side.
C. The bromine atoms must go through a liquid state before becoming a gas.
D. There is more mass represented on the right side of the equation than on the left side.
E. The bromine atoms on the right side of the equation are not bonded to another element.
Answer (1)
The equation is unbalanced because the number of bromine atoms differs on each side.
Unbalanced equations violate the law of conservation of mass.
More mass on the right side makes the reaction impossible as written.
The correct answer is D: There is more mass represented on the right side of the equation than on the left side. $\boxed{D}
Explanation
Analyzing the Chemical Equation Let's analyze the given chemical equation: A g B r ( s ) r i g h t a rro w A g ( s ) + B r 2 ( g ) . We need to determine why this unbalanced equation is not possible. A balanced chemical equation must have the same number of atoms of each element on both sides of the equation, representing the conservation of mass.
Counting Atoms On the left side of the equation, we have 1 silver (Ag) atom and 1 bromine (Br) atom. On the right side, we have 1 silver (Ag) atom and 2 bromine (Br) atoms. Therefore, the equation is unbalanced because the number of bromine atoms is not the same on both sides.
Evaluating the Options Now, let's evaluate the given options:
A. There are more substances on the right side of the equation than on the left side. This statement is not necessarily true for all unbalanced equations. The key issue is the conservation of mass, not the number of substances.
B. There is a gas on the right side of the equation but not on the left side. The presence of a gas doesn't inherently make an equation unbalanced. It's the number of atoms that matters.
C. The bromine atoms must go through a liquid state before becoming a gas. The state of matter (solid, liquid, gas) doesn't determine whether an equation is balanced.
D. There is more mass represented on the right side of the equation than on the left side. This is the correct answer. Since there are more bromine atoms on the right side, the mass is not conserved, making the equation impossible as written.
E. The bromine atoms on the right side of the equation are not bonded to another element. The bromine atoms on the right side are bonded to each other, forming B r 2 .
Conclusion The correct answer is D. The unbalanced equation violates the law of conservation of mass because there are more bromine atoms on the right side of the equation than on the left side. Therefore, there is more mass represented on the right side of the equation than on the left side.
Examples
Consider a simple reaction where silver bromide decomposes into silver and bromine gas. In real life, you can't create or destroy atoms. If you start with a certain amount of silver bromide, the mass of silver and bromine produced must equal the mass of the silver bromide you started with. This principle is crucial in various applications, such as calculating the yield of a chemical reaction or ensuring that chemical processes are safe and efficient.
