Chemistry Practice Problems Identifying Reaction Order Practice Problems Solution: Barium-122 has a half-life of 2 minutes. You just ...

🤓 Based on our data, we think this question is relevant for Professor McAbee's class at CSULB.

Solution: Barium-122 has a half-life of 2 minutes. You just obtained a sample weighing 10.0 grams. If takes 10 minutes to set up the experiment in which barium-122 will be used. How many grams of barium-122 will be left when you begin the experiment?a. 0.313 g remainb. 0.625 g remainc. 0.00 g remaind. 50.0 g remaine. 2.00 g remain 

Problem

Barium-122 has a half-life of 2 minutes. You just obtained a sample weighing 10.0 grams. If takes 10 minutes to set up the experiment in which barium-122 will be used. How many grams of barium-122 will be left when you begin the experiment?

a. 0.313 g remain

b. 0.625 g remain

c. 0.00 g remain

d. 50.0 g remain

e. 2.00 g remain 


Solution

We’re being asked to calculate the mass of barium-122 remaining from 10.0 g Ba-122 after 10 minutes. The half-life of Ba-122 is 2 minutes.


Since barium-122 has a half-life, it is a radioactive isotope. Recall that radioactive isotopes follow first-order kinetics.


The integrated rate law for a first-order reaction is as follows:


ln[A]t=-kt+ln[A]0


where: 

[A]t = concentration at time t

k = rate constant

t = time

[A]0 = initial concentration


Solution BlurView Complete Written Solution