Question

For the Bradford assay, the instructor will make a Bradford reagent dye by mixing 50 ml of 95% v/v ethanol with 100 mg of Coomassie Blue followed by the addition of 100 ml of 85% v/v phosphoric acid. This entire mixture is then diluted to 1 liter with water. What is the final concentration of phosphoric acid?

Answer 1

4.25% is the final concentration of phosphoric acid.

Step-by-step explanation:

Initial concentration of phosphoric acid =
`C_1=85\%=0.85`

Initial volume of phosphoric acid =
`V_1=50 mL`

Final concentration of phosphoric acid =
`C_2=?`

Final volume of phosphoric acid =
`V_2=1 L=1000 mL`

( 1L = 1000 mL)

`C_1V_1=C_2V_2`

`C_2=(C_1times V_1)/(V_2)`

`=(0.85* 50 mL)/(1000 mL)=0.0425=4.25%`

4.25% is the final concentration of phosphoric acid.