Question

Lana balanced an equation so that the result was 2C2H3Br + 5O2 → 4CO2 + 2H2O + 2HBr. Which most likely represents the starting equation?

2C4H3Br + 5O2 → 4CO2 + 2H2O + 2HBr
C2H3Br + 5O2 → 4CO2 + H2O + 2HBr
C4H3Br + O2 → CO2 + H2O + HBr
C2H3Br + O2 → CO2 + H2O + HBr

Answer 1

Answer: The correct answer is:

`C_2H_3Br+O_2\rightarrow CO_2+H_2O+HBr`

Step-by-step explanation:

`2C_2H_3Br+5O_2\rightarrow 4CO_2+2H_2O+2HBr`

The given chemical reaction is balanced that is there are equal numbers of atoms of each elements on both sides.

So, the starting chemical equation of the this chemical equation can be written as just by removing the stoichiometric coefficients of all compounds appearing in the chemical reaction.:

`C_2H_3Br+O_2\rightarrow CO_2+H_2O+HBr`

Answer 2

The correct option is option D which is C2H3Br + O2 → CO2 + H2O + HBr.

Step-by-step explanation:

• The balanced equation is: 2C2H3Br + 5O2 → 4CO2 + 2H2O + 2HBr
• In the equation one reactant is C2H3Br. But in option 1 and 3 reactant is C4H3Br which is changed from balanced equation.
• So option 1 and 3 are rejected on the bases of reactant change.
• Now equations of option 2 and 4 can be correct.
• In option 2, there are already coefficient with some reactant and products. So it can be less probable original equation.
• Equation of option 4 is correct one which is correct without coefficients.