A Question About Salt/Sodium Levels?

When you add salt to water to cook such things as potatoes/vegetables or pastas, or such food items; how much of the salt enters the food, and how much remains in the water? Let’s say for sake of this question, that I add1/2 teaspoon to four cups of water with four medium peeled cut up potatoes in the water, boil them until they are done then drain off the water; how much salt would be in the water I had poured off and how much would have entered the food I boiled? Thank you for anyone’s cooperation in this matter. Respectfully Submitted.