Question

Max experimented by adding red-dyed salt water to clear freshwater. He noticed that the red water sank below the clear water. Which of the following statements explains why this happened?

Adding salt to water increases its temperature.

Adding salt to water makes it denser.

Adding salt to water decreases its temperature.

Adding salt to water makes it less dense.

Answer 1

Adding salt to water makes it denser.

Dissolved salt increases the mass per unit volume of the water, so the salty (red) water is denser than the clear freshwater and therefore sinks below it.