Density is a unit of measurement defined by how much matter takes up a certain amount of volume or space, therefore, when salt is added to water the following occurs:
A) The volume or space that the water takes up has very slightly increased but
B) The mass of the water has very greatly increased due to the salt ions (Ions being atoms with either extra electrons or missing electrons) having been attracted to the water and bonded themselves very closely to the water molecules.
The mass of the water has increased faster than the volume or space that it requires to take up, therefore the density of the water with salt in it is greater than normal water because for a certain volume of water there is more material or matter in salt water than there is in the same volume of normal water. So basically, in the very simplest answer would be "Because there's more stuff than just water in it." And most of that other "stuff" is heavier than pure water.
If you need something visual, picture (or try) this: You have 2 glasses filled with the same amount (volume) of freshwater. They both have the same density. Now, to one of the units, add 25 grams of table salt and stir it until it is all dissolved. Once dissolved, you will find that the volume of this unit is still the same (one unit) but if you weigh it, it is now 25 grams heavier than the remaining freshwater sample. Therefore the unit with the salt is now denser than the freshwater unit.
(Basically, think of fresh water as marbles in a cup. There are gaps between the marbles. When you add salt, the gaps are filled in, making it denser.)
Need something more scientific than just "because there's more stuff, it's heavier"? Check out what this science teacher has to say:
Firstly, you need to understand that when salt (sodium chloride NaCl) is added to water it disassociates into two charged ions; Na+ and Cl-
The water molecule is shaped much like this:
O
/ \
H H
The oxygen has two lone pairs of electrons exposed on the top, so it attracts anything positive (e.g. Na+). The Hydrogen atoms are sharing their one electron with each of the covalent bonds with the oxygen atom. This exposes the positively charged nucleus and attracts negatively charged particles (e.g. Cl-).
This has the overall effect of pulling the water molecules closer together (but not chemically bonding) in salt water than they would normally be in fresh water. We define density as being related to the number and size of particles in a given volume. The overall pulling together of the water molecules means that more water molecules will fit into a smaller space.
Salt water is more dense than fresh water due to the presence of dissolved salts such as sodium chloride. This increased density allows objects to float higher in salt water compared to fresh water.
Fresh water is less dense than salt water, so it floats on top of the more dense salt water. This is due to differences in their salinity levels, with salt water being more concentrated. The less dense fresh water sits above the denser salt water due to the principle of buoyancy.
Fresh water is less dense than salt water because it has fewer dissolved ions. This difference in density causes fresh water to float on top of salt water, creating distinct layers. Salt water is more concentrated with ions, making it denser and causing it to sink below the less dense fresh water.
Things float in water if they are less dense than the water they are floating in. Putting salt in the water makes it more dense, so things that are a little more dense than ordinary water float in salt water.
Ships sink more in fresh water than in salt water because fresh water is less dense than salt water. This means that a ship will displace less water in fresh water compared to salt water, leading to less buoyancy and a higher likelihood of sinking. Additionally, fresh water lacks the buoyant force provided by dissolved salts in salt water.
Cold water is more dense.
salt water is more dense than tap water
Salt water will be more dense than the water, but less dense than the salt.
Salt
Because of the salt - salt is denser than water.
Salt water in more dense.The higher the salinity, the denser it is.
Seeds grow in regular water and not in salt water because regular water is more healthy than salt water.
The density of liquids really depends on the suspended matter in it. If you have really dense concentration of salt in water, yes it could be denser than an egg. If you have merely a weak solution of salt, then the egg is denser... it depend on how much salt you have in the water.
An egg floating in salt water. The salt makes the water more dense. Since the egg is less dense it floats!
Salt water is more dense than fresh water due to the presence of dissolved salts such as sodium chloride. This increased density allows objects to float higher in salt water compared to fresh water.
Because the salt water is more dense than the egg.
Salt water as it is more dense than water.