Question

The rate constant for this first-order reaction is 0.0442 s−¹ at 300 °C.

A⟶products
If the initial mass of A is 18.00 g, calculate the mass of A remaining after 0.791 min.
Mass of A: ___ g.

Answer 1

To calculate the mass of A remaining after 0.791 min in a first-order reaction, we can use the equation [A]t = [A]0 * e^(-kt), where [A]t is the concentration of A at time t, [A]0 is the initial concentration of A, k is the rate constant, and t is the time. Substituting the given values, the mass of A remaining after 0.791 min is calculated to be 3.39 g.

Step-by-step explanation:

To calculate the mass of A remaining after 0.791 min, we can use the first-order rate equation: ln([A]t/[A]0) = -kt Where [A]t is the concentration of A at time t, [A]0 is the initial concentration of A, k is the rate constant, and t is the time. Rearranging the equation to solve for [A]t: [A]t = [A]0 * e^(-kt) .

Given that the initial mass of A is 18.00 g and the rate constant is 0.0442 s^-1 at 300 °C, we can calculate the mass of A remaining after 0.791 min: [A]t = 18.00 g * e^(-(0.0442 s^-1 * 0.791 min * 60 s/min)) [A]t = 18.00 g * e^-1.665 [A]t = 18.00 g * 0.188 [A]t = 3.39 g Therefore, the mass of A remaining after 0.791 min is 3.39 g.