How do you measure the density of salt water

I'm doing a science fair project on how the different types of salt affect the density of the water.

I'm only in middle school so can you explain it easy? Thanks.

step 1: you need to get a container, then weigh it when it is empty. This will give you your zero for the water. For example when you weigh the beaker it comes to 20 grams, take a note of this because you will need to subtract this from your results.

step 2: you need a control. fill the beaker will water and measure it. This will give you the mass of the water and beaker, say you get 150 grams. This is when you need step 1, subtract the beaker mass in this case 20 grams from the 150 gram reading. This leaves the mass of the water.

step 3: use density = mass/volume (/ means divide)
the volume is the volume of the water in the beaker.
Record this result. It should be around 1 gram per cubic centimetre (1g/cm^3)

in the example say the volume was 150cm^3 then:

density = 150 grams / 150 cm^3

density = 1g/cm^3

step 4: add salt and measure the mass of water + salt + beaker the subtract beaker mass then apply step 3

step 5: record and repeat until your done.

hope this helps.

You can measure density directly with a hydrometer, or indirectly by weighing a specific volume of the mix.