The following solutions are combined:

20 mL of 0.50 M TRIS buffer, pH 7.0

10 mL of 0.25 M KCl

90 mL of 0.30 M sucrose

150 mL dH2O

Calculate the concentration of sucrose in the final solution.

1 answer

To calculate the concentration of sucrose in the final solution, you first need to determine the total volume of the solution after all components have been combined and then calculate the amount of sucrose added to that volume.

Step 1: Calculate the total volume of the final solution

  • Volume of TRIS buffer: 20 mL
  • Volume of KCl: 10 mL
  • Volume of sucrose: 90 mL
  • Volume of dH2O: 150 mL

Total volume = 20 mL + 10 mL + 90 mL + 150 mL = 270 mL

Step 2: Calculate the amount of sucrose in the solution

We have 90 mL of a 0.30 M sucrose solution.

To find the number of moles of sucrose in this solution, we can use the formula:

\[ \text{moles of sucrose} = \text{concentration (M)} \times \text{volume (L)} \]

First, convert the volume from mL to L:

\[ 90 , \text{mL} = 0.090 , \text{L} \]

Now, substitute the values into the equation:

\[ \text{moles of sucrose} = 0.30 , \text{M} \times 0.090 , \text{L} = 0.027 , \text{moles} \]

Step 3: Calculate the concentration of sucrose in the final solution

Now, we need to find the concentration of sucrose in the final 270 mL (or 0.270 L) of the solution:

\[ \text{concentration of sucrose} = \frac{\text{moles of sucrose}}{\text{total volume (L)}} \]

Substituting the known values:

\[ \text{concentration of sucrose} = \frac{0.027 , \text{moles}}{0.270 , \text{L}} = 0.100 , \text{M} \]

Final Answer

The concentration of sucrose in the final solution is 0.100 M.