Concentrations and dilution
The fraction of concentrate is concentrate divided by the total mixture.
- The fraction of concentrate is concentrate divided by the total mixture.
- Adding water leaves the amount of concentrate unchanged but increases the total.
- Use the new ratio to find the required water, then subtract the water already present. Assume volumes add.
Example 1
A mixture contains 20 ml concentrate and 40 ml water. Water is added until concentrate : water = 1 : 4. How much water is added? Assume volumes add.
Example 2
A mixture contains 25 ml concentrate and 75 ml water. Water is added until concentrate : water = 1 : 5. How much water is added? Assume volumes add.
Remember
Use the worked steps to check your method, not just the final answer.
Your turn
A mixture contains 30 ml concentrate and 120 ml water. Water is added until concentrate : water = 1 : 6. How much water is added? Assume volumes add.
Check answer
The concentrate fraction falls from
A mixture contains 35 ml concentrate and 175 ml water. Water is added until concentrate : water = 1 : 7. How much water is added? Assume volumes add.
Check answer
The concentrate fraction falls from
A mixture contains 40 ml concentrate and 80 ml water. Water is added until concentrate : water = 1 : 4. How much water is added? Assume volumes add.
Check answer
The concentrate fraction falls from
A mixture contains 45 ml concentrate and 135 ml water. Water is added until concentrate : water = 1 : 5. How much water is added? Assume volumes add.
Check answer
The concentrate fraction falls from
A mixture contains 50 ml concentrate and 200 ml water. Water is added until concentrate : water = 1 : 6. How much water is added? Assume volumes add.
Check answer
The concentrate fraction falls from
A mixture contains 30 ml concentrate and 120 ml water. Water is added until concentrate : water = 1 : 6. How much water is added? Assume volumes add.
AnswerThe concentrate fraction falls from
A mixture contains 35 ml concentrate and 175 ml water. Water is added until concentrate : water = 1 : 7. How much water is added? Assume volumes add.
AnswerThe concentrate fraction falls from
A mixture contains 40 ml concentrate and 80 ml water. Water is added until concentrate : water = 1 : 4. How much water is added? Assume volumes add.
AnswerThe concentrate fraction falls from
A mixture contains 45 ml concentrate and 135 ml water. Water is added until concentrate : water = 1 : 5. How much water is added? Assume volumes add.
AnswerThe concentrate fraction falls from
A mixture contains 50 ml concentrate and 200 ml water. Water is added until concentrate : water = 1 : 6. How much water is added? Assume volumes add.
AnswerThe concentrate fraction falls from