2.4g Na(100gsoln/0.05g Na) (1ml/1g) (1L/1000ml) = 4.8 Liters
First you take the 2.4 g that is given and find out how much solution that is using the mass percent 0.05%. You get the grams of water but you want the volume so you used density of water and convert what you get into liters.
This problem involves percent concentration by mass.
You have a solution that is 99.95% water and 0.050% sodium by mass.
First, you need to weigh a liter of your solution. Let’s say your solution weighs 1000g.
1000*0.9995=999.50g of water per liter
1000*0.00050=0.50g of sodium per liter
To find the number of liters you need to consume to ingest at least 2.4g of sodium, simply divide 2.4 by 0.5 to get 4.8 liters of solution.
When looking to create a solution, use this formula for percent concentration by mass: mass solute/mass solutionX100.
Hope this helps!