Is salt a solution or mixture

Depends on how you use the salt.

If you mix it with water it's a mixture because you can still seperate it, and it is still salt and water.

Salt is a compound, with the chemical name "Sodium chloride"

and the chemical formula NaCl.

Each molecule of salt is an atom of sodium electrically bound to

an atom of chlorine.

The chemical properties of salt are completely different from the

chemical properties of either element in its molecule. In fact,

sodium and chlorine are both toxic and corrosive, i. e., poison,

but as long as the salt is still salt, you can safely eat it!

There's nothing physical or mechanical, like spinning or filtering,

that you can do to salt to separate the sodium from the chlorine.

That takes electrical or chemical processes, and once you separate

them, you wind up with two substances that are both dangerous.

If you put salt into a jar with some sand and shake it up, then you

have a mixture. The salt is still salt and the sand is still sand, and

they can be separated quite easily.

If you put some salt in some water, and stir it up so that the salt

dissolves, then you have a salt solution. Some of the salt

molecules actually come apart in it, and there are sodium ions

and chlorine ions in the water. When that happens, the water

begins to conduct electric current very nicely, and if you DO

pass current through it, you get sodium collecting at the end

of one wire, and chlorine collecting at the other wire. But if you

just let it set there in the sun, or heat the solution on the stove,

then once the water evaporates, you have plain old salt again

in the jar.