Final answer:
The rate of change of A in the reaction 3A → B+2C, when B forms at 0.125 m/s, is −0.375 m/s, as A is consumed three times as fast as B forms, according to the stoichiometry of the reaction.
Step-by-step explanation:
The question asks for the corresponding rate of change of A for the reaction 3A → B+2C. Given the rate of formation of B is 0.125 m/s, we can find the rate of disappearance of A by looking at the stoichiometry of the reaction. The reaction shows that 3 moles of A produce 1 mole of B. Therefore, the rate at which A is consumed is three times the rate of formation of B.
The calculation is as follows: rate of disappearance of A = rate of formation of B × (moles of A/moles of B) = 0.125 m/s × 3 = 0.375 m/s. However, because A is being consumed, the rate of its disappearance is negative, making the correct answer −0.375 m/s, which corresponds to Option 1.