Dilution Problem - Mixed category
9. Altering Product Strength 9.1) Dilution 9.1.1) Dilution
9.1.1.1) Find initial concentration in dilution Challenging 1
Total tried: Correct: Wrong:
Calculate the quantity of solvent you need to add into 47.5 mL of a 26.25 % solution to prepare a 9.24 % solution?
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lb equals 87.5 mL kg
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This is a volume expansion or concentration dilution type problem. The essential formula is `Q_1C_1 = Q_2C_2`.
Here,
`Q_1` = initial quantity = `47.5\quadmL`.
`C_1` = initial concentration = `26.25\quad%`
`Q_2` = final quantity = `?\quad mL`.
`C_2` = final concentration = `9.24\quad %`
Therefore, rearranging the formula, we get:
`Q_2 = (Q_1 × C_1)/(C_2)` `therefore Q_2 = (47.5 × 26.25) /9.24=135\quad mL` in nearest whole number.
Now, subtract the initial quantity of the solution (`47.5\quadmL`) from this final quantity (`135\quadmL`) to determine the amount of solvent to be added: `135\quadmL-47.5\quadmL=87.5\quadmL`. (Ans)