probably a supersaturated solution if you heat it to dissolve all of the salt
You have said yourself that is about 200 grams.
The first solution (500 g/L) is more concentrated than the second (200 g/L).
200 grams X 0.10 = 20 grams
Only if you have pure water in mind: 200 cc = 200 milliliters of pure water weigh 200 grams.
200 grams of water is approximately equals to 219 mili litre.
Add 200 grams of the salt to 800 g of water, mix and dissolve, and you've got your desired 20% solution.
That is 40 teaspoons.
That is approximately 2/5 of a pint
It can only be in kilometers
238 grams of water equals 1 cup. So 200 grams of water would be a little over 3/4 cup or around 7/8 of a cup.
On earth, 200 grams of mass weighs 0.441 pound = 7.055 ounces. (rounded)
There are 200 grams in 200 grams.