calculations for college practical

[arcticchris]

Help please i am a first year btec nvq3 student.

we are making potassium permanganate solution 150ml.

The patient should make a dose of 5ml of solution made up to 500ml with tap water with a final concentration of 1 in 8000.

How do i get the quantity of potassium permanganate powder in mg and the strength of the solution before dilution by the patient.

I got 1875mg in 150 ml and 0.0125% is this right?

[PHARMAC1ST]

You've had a go so i will help.
final concentration = 1g in 8000ml
if patient is using total of 500ml then that would mean that 1g/16 in 500ml
1000mg/16 = 62.5mg in 500ml (but we use 5ml of potas perm therefore we need 62.5mg in 5ml)
62.5mg in 5ml
therefore 1875mg in 150ml (x 30)
expressed as percentage
62.5mg in 5ml
125mg in 10ml
1250mg in 100ml
1.25g in 100ml therefore 1.25%w/v

Hope it helps