Question

when salt is added to water the volume of the salt solution remains same why​

Answer 1

Answer:

You need to understand one property of atom or molecules that they are packed loosely in liquids and more so in gases. So there is lot of space between any two given molecules, therefore when you mix salt particles into the solution, they settle between the empty spaces, hence the volume remains the same. But as you may have figured out, the density of the solution increases

Answer 2

Answer:

Because salt is adjusted in the intermolcular spaces between the water molecules