6 posts • Page 1 of 1
I think you're referring to when approximating x. You omit the x in the denominator just to approximate x. Once you find the x, divide it by the molarity given. If it is smaller than 5%, it is a good approximation. I hope that answers your question!
You're in the clear to approximate without using x if it is 10^-5, 10^-6 and so on. If it is 10^-3 you leave x and use the quadratic equation. But if it is 10^-4 you can take out x and to be sure you would then check if you're in the 5% range.
I also just want to mention what another student told me today at a review session. You can't just blindly approximate if you see the Ka or Kb value is 10^-5. Take the extra 2 minutes and make sure that it is actually 5% because if the initial value is smaller than 10^-5 it will mess up your calculations.
Who is online
Users browsing this forum: No registered users and 1 guest