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BISC110/S13: Series 1 Lab 1 Boot Camp: Difference between revisions
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BISC110/S13: Series 1 Lab 1 Boot Camp (view source)
Revision as of 09:14, 11 January 2013
, 11 January 2013→PART IV: Dilutions
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'''1. Ratio Method''' | '''1. Ratio Method''' | ||
This type of dilution describes the ratio of the solute to the total volume of the dilute solution. For example, to make a 1:10 dilution of a 1M NaCl solution, you would mix one part of the 1M solution with 9 parts of solvent (probably water), for a total of ten parts. If you needed 10mL of the 1:10 dilution, then you would mix 1mL of the 1M NaCl with 9mL of water yielding a total volume of 10mL. If you needed 100mL of the 1:10 dilution, then you would mix 10mL of the 1M NaCl with 90mL of water yielding a total volume of 100mL. The new concentration of NaCl in both solutions is determined by multiplying the stock concentration by the dilution ratio: | This type of dilution describes the ratio of the solute volume to the total volume of the dilute solution. For example, to make a 1:10 dilution of a 1M NaCl solution, you would mix one part of the 1M solution with 9 parts of solvent (probably water), for a total of ten parts. If you needed 10mL of the 1:10 dilution, then you would mix 1mL of the 1M NaCl with 9mL of water yielding a total volume of 10mL. If you needed 100mL of the 1:10 dilution, then you would mix 10mL of the 1M NaCl with 90mL of water yielding a total volume of 100mL. The new concentration of NaCl in both solutions is determined by multiplying the stock concentration by the dilution ratio: | ||
1M NaCl x 1/10 = 0.1M NaCl | 1M NaCl x 1/10 = 0.1M NaCl | ||
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#Using a clean pipette tip, remove 100 μL of solution from the 1/16 tube, and discard it in the sink. You now have four tubes containing 100 μL of four different working concentrations of your reagent. Observe the color intensity of the four solutions and record in your lab notebook. Also, observe the relative volumes of the four solutions. If they are different from each other, then inaccurate pipetting has occurred. Save these dilutions for use next week.<BR> | #Using a clean pipette tip, remove 100 μL of solution from the 1/16 tube, and discard it in the sink. You now have four tubes containing 100 μL of four different working concentrations of your reagent. Observe the color intensity of the four solutions and record in your lab notebook. Also, observe the relative volumes of the four solutions. If they are different from each other, then inaccurate pipetting has occurred. Save these dilutions for use next week.<BR> | ||
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=='''Assignments'''== | =='''Assignments'''== | ||
