You usually weigh salt to assess how much you have, but you could measure its volume instead of its weight if you wish. It is always sold by weight in my experience, but when cooking, it is usually measured by 'so many level teaspoons '
milligrams
let the water evaporate and measure the salt that is left in the jar
Just measure out one gram and multiply by 10.
how do you measure the salt level in an ocean,creek,and river?
Yes
by volume.
To measure one gram of salt, you can use a digital kitchen scale for the most accurate measurement. If a scale isn't available, you can use measuring spoons, where one teaspoon of salt typically weighs about 5-6 grams, so you can estimate by using roughly one-fifth of a teaspoon. Alternatively, you can use a small container or scoop that you know the weight of to help gauge the amount.
A concentration of 1 ppm (parts per million) of salt in water means that there is one part of salt for every one million parts of water. It is a measure of the amount of salt present in the water and is commonly used to express very low concentrations.
It depends on whether you wish to measure its length, its volume or its mass.
A "pinch" is just that... such as a pinch of salt in a recipe. I was told at one point that a Pinch works out to about 1/8th of a teaspoon, but it's probably even a little less than that. To do "a pinch of salt", one would pinch some salt between their fingers and put it in the recipe.
salt levels in an aqueous solution
tsp