Serial Dilution

A dilution represents the ratio of the concentrated/ stock solution to the total final volume /weight of both the solute and solvent. Serial dilutions involve the use of a series of dilutions to arrive at the desired concentration instead of making one large dilution as with simple dilution. You begin with a solution lets call it solution A, which has a known volume and then solute will be taken from this and diluted with a solvent forming solution B. Solute will then be taken from solution B and diluted with a solvent to form solution C. Similar steps can be followed until you get the desired final volume. Serial dilutions allows the use of small quantities of solute/solvent to get dilutions which are relatively large. Before you carry out a serial dilution in the lab you will need to know:

*The concentration of the original, stock solution

*The desired concentration of your dilute solution

*The dilution factor and the number of dilution to be made to get the desired concentration

Lets first have a quick review of dilution factors:

A 1:10 dilution represents 1 unit volume of solute is dissolved in 9 unit volumes of solute to get a total solution volume of 10 units.

Carrying out a serial dilution in the lab

Take some solute, add solvent from this to make the next dilution. Follow this stepwise arrangement until you have reached your desired concentration .*When carrrying out experiments in the lab be sure to mix your thoroughly

For serial dilutions the following equation applies:


original concentration/New concentration= Overall dilution factor

To get the overall concentration simply multiply all the concentartions

Example:


If a serial dilution consisting of two 1:10 dilutions are carried out, to get the overall dilution factor:





1/10 * 1/10=1/100

Action Breeds Motivation

Discover a way to finally banish unproductive days and find yourself continually motivated and productive. Learn the answer to taking the action necessary for a life of productivity in the following 3 examples.

Problem #1: You hit a brick wall. No matter what aspect of our life we are thinking of right now, there are times when we come to a point where we just don't know what we must do next. We are faced with a situation where we cannot see the next step. What are we supposed to do next?
Answer: Instead of remaining paralyzed, list several options for the next possible steps of action. Instead of doing nothing and wasting all the precious return of the work already completed, take action.
Write out the list of possible actions that could be taken. Write the list till you come to something that you could do immediately and begin.
The action of beginning is usually the action that breaks the paralysis of unproductivity!

Problem #2: We have no desire to do the next thing. We've come to a place where we haven't got the ambition to do what it takes. We don't really even want an answer as to why we aren't motivated - we just want to do nothing!
Answer:It's time to review your objectives for doing this project. Why did you choose to start this project? What are the benefits of completing this project?
When you have reviewed your reasons for doing this project go back to your list of action steps (you do have one for each project, don't you?) and choose one action step. Begin on that one action and watch your lack of motivation fly out the window!

Problem #3: Too many things need our attention at once! We are bombarded with so many things that must be done we cannot see ourselves ever getting any of them done! Life is so busy that it doesn't seem to matter where I put my effort; something else screams louder and calls me away. This leaves me running in circles and being unproductive.
Answer: When all projects and demands are due now or past due it's time to jot down each task and the steps you must take to complete them. On your new task list put each job in order of importance and devote 15 - 30 minutes to each of the #1 jobs in each category.
As you begin to see progress the enormity of your responsibilities begins to melt away and you have a focus in each area to complete all the demands on your time.
The bottom line: when you lose motivation, regain it quickly by taking action!

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