Making Molar Solutions And Dilution Lab
Making Molar Solutions and Dilutions
Objectives:
After performing this lab, the student should be able to:
• Calculate grams of solute and correctly prepare a molar solution.
• Prepare parallel and serial dilutions using C1V1 = C2V2
• Distinguish a parallel dilution from a serial dilution.
• Determine whether a parallel or serial dilution should be used in a given situation.
• Use a microcentrifuge to make a pellet.
Making Molar Solutions and Dilutions
A major job of any biotechnician is the preparation of solutions. Accuracy is of the utmost importance. An incorrectly prepared solution can destroy months of hard work or cost companies thousands of dollars. Therefore, several safeguards are in place in most SOPs (Standard …show more content…
Repeat steps 1 – 6 to make 20 mL of a 2 M solution of magnesium sulfate (F.W. 246.48) in a small flask or beaker.
PART B: MAKING PARALLEL DILUTIONS
A dilution consists of adding addition solvent (usually water) to a solution to reduce its concentration.
Dilution Terminology
a) One part food coloring combined with 9 parts water means the food coloring is 1 part in 10 mL total volume or 1/10 food coloring. The denominator in an expression with a slash (/) is the total volume of the solution.
b) An undiluted substance, by definition, is referred to as 1/1.
c) When talking about dilutions, the symbol : means parts. If 1 mL of food coloring is combined with 9 mL of water, that is 1 part food coloring plus 9 parts water or 1:9 food coloring to water. A dilution of 1 part plus 9 parts is not referred to as a 1:10 dilution.
d) a 1:2 dilution means there are 3 parts total volume, while a 1/2 dilution means there are 2 parts total volume. (The parts can be of any unit. A 1 mL to 2 mL produces the same dilution as 1 oz. to 2 oz.)
Concentration Dilutions
To produce a given amount of a less concentrated solution from a more concentrated stock solution the following formula is used: C1V1 = C2V2
C1 = original concentration (con. of stock …show more content…
Measure 10 mL of a 1 M solution of hydrochloric acid (HCl). Be sure to wear goggles and gloves when working with acids. Place the acid in a small, labeled test tube.
2. Calculate how much of the acid to mix with water to produce 10 mL of a 0.1 M solution, a 0.01M solution and a 0.001
M solution. Show your calculations in your notes. For a serial dilution the original volume is the dilution before it not the stock solution. (i.e. make the 0.01 M from the 0.1 M solution and the 0.001 M from the 0.01 M)
3. Label 3 test tubes with the concentration from step 2 and add the correct amount of water to each one. Remember the
AAA rule (always add acid) when working with acids. Never add water to acid, always add acid to water.
4. Add the correct amount of acid to each test tube and stir with a stirring rod.
5. Measure the pH of each solution using the pH meter. If you are the first group to use the meter. Calibrate it using the buffers and SOP provided.
6. Record the pH of each dilution and record it in your notebook.
Making Molar Solutions and
Objectives:
After performing this lab, the student should be able to:
• Calculate grams of solute and correctly prepare a molar solution.
• Prepare parallel and serial dilutions using C1V1 = C2V2
• Distinguish a parallel dilution from a serial dilution.
• Determine whether a parallel or serial dilution should be used in a given situation.
• Use a microcentrifuge to make a pellet.
Making Molar Solutions and Dilutions
A major job of any biotechnician is the preparation of solutions. Accuracy is of the utmost importance. An incorrectly prepared solution can destroy months of hard work or cost companies thousands of dollars. Therefore, several safeguards are in place in most SOPs (Standard …show more content…
Repeat steps 1 – 6 to make 20 mL of a 2 M solution of magnesium sulfate (F.W. 246.48) in a small flask or beaker.
PART B: MAKING PARALLEL DILUTIONS
A dilution consists of adding addition solvent (usually water) to a solution to reduce its concentration.
Dilution Terminology
a) One part food coloring combined with 9 parts water means the food coloring is 1 part in 10 mL total volume or 1/10 food coloring. The denominator in an expression with a slash (/) is the total volume of the solution.
b) An undiluted substance, by definition, is referred to as 1/1.
c) When talking about dilutions, the symbol : means parts. If 1 mL of food coloring is combined with 9 mL of water, that is 1 part food coloring plus 9 parts water or 1:9 food coloring to water. A dilution of 1 part plus 9 parts is not referred to as a 1:10 dilution.
d) a 1:2 dilution means there are 3 parts total volume, while a 1/2 dilution means there are 2 parts total volume. (The parts can be of any unit. A 1 mL to 2 mL produces the same dilution as 1 oz. to 2 oz.)
Concentration Dilutions
To produce a given amount of a less concentrated solution from a more concentrated stock solution the following formula is used: C1V1 = C2V2
C1 = original concentration (con. of stock …show more content…
Measure 10 mL of a 1 M solution of hydrochloric acid (HCl). Be sure to wear goggles and gloves when working with acids. Place the acid in a small, labeled test tube.
2. Calculate how much of the acid to mix with water to produce 10 mL of a 0.1 M solution, a 0.01M solution and a 0.001
M solution. Show your calculations in your notes. For a serial dilution the original volume is the dilution before it not the stock solution. (i.e. make the 0.01 M from the 0.1 M solution and the 0.001 M from the 0.01 M)
3. Label 3 test tubes with the concentration from step 2 and add the correct amount of water to each one. Remember the
AAA rule (always add acid) when working with acids. Never add water to acid, always add acid to water.
4. Add the correct amount of acid to each test tube and stir with a stirring rod.
5. Measure the pH of each solution using the pH meter. If you are the first group to use the meter. Calibrate it using the buffers and SOP provided.
6. Record the pH of each dilution and record it in your notebook.
Making Molar Solutions and