There are several reasons why the boiling point changes when salt is added to water.
Firstly you have to understand the heat capacity (how much heat is needed to heat a substance) of water and salt. Water has a high heat capacity which means that it needs a lot of heat to warm the liquid up. However, when salt is added to water the heat capacity is lower, therefore less heat is needed to warm the liquid up.
Secondly, you have to observe the amount of salt added to water. So, if you compare 100ml of water to 100ml of salt water - what percentage of this solution is salt? (say 40% salt and 60% water). This is important because, the heat capacity of the 60% of the water in salt water, is 40% less than the 100% water, so it takes less energy to heat up the mixture.
Anyway, going back to the question, yes the boiling point does change slightly when salt is added. In fact the boiling point of water will increase with any impurity in the water. With Salty water the boiling point increases and freezing point decreases (but there is no definite boiling point for salt water because it depends on the ratio of salt to water).
Thirdly, when you add salt to water you change the molecular-level of water (also called colligative property). The concentration of water in salt water is less, so the vapour pressure of salt water is less and that's why the temperature must increase.
Lastly, when salt is added to H2O, the NaCl (salt- Sodium Chloride) interferes with the H and the O. This stops the liquid from behaving the way it usually does. Like when you freeze salt water...
When a solute (salt) is added to a solvent (water), the melting point decreases and the boiling point increases. The boiling point increases because for boiling to occur, the salt must come out of solution (undissolve). This requires a decrease in entropy. Effectively, it requires energy for the salt to come out of solution, so more heat (energy) must be added to the solution before the salt comes out of solution, allowing the water to boil.
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Yes, there is a change in the temperature when salt is heated to boiling temperature. The temperature increases from 100 degree celsius to 102 degree celsius.
The water molecules find themselves more attracted to the salt ions than pure water is to itself. In order to boil, the water molecules must gain enough kinetic energy to compensate for the greater intermolecular forces produced by the dissolved salt.
For dissolutions there are two important energies that have to be regarded:
the lattice energy that keeps the ions of the salt together and
the enthalpie of dissolution that is freed when an ion is solvated
When you dissolve a salt in water you have to break the ions away from the crystal chunk and maybe you know salt (NaCl) is made of positive Na+ and negative Cl- ions - positive and negative are attracted to each other (like magnets) and for a break up you need energy (just like magnets, too)
When the ions are released, they are getting a kind of sleave of water molecules which releases some energy (the enthalpie of dissolution + hydration)
Now there are three possibilities:
1. The lattice energy equals the enthalpie of dissolution - so no change in temperature occurs
2. The enthalpie of dissolution is higher than the lattice energy - so the energy is freed in the form of warming
3. The case of NaCl: the lattice energy is (slightly) higher - so the system takes the energy that is missing for the break up from the liquid around and cools down your boiling water
When you add salt to boiling water the boiling point is increased.
The boiling point and freezing point of water raises when you add salt.
salt raises the boiling point
Yes, Salt also lowers the freezing point of water, and lowers the boiling point of water. Add salt to a boiling pot of water and it immediately boils faster/harder at the location that the Salt hit the water.
The quantity of salt added to water is under your control and it will change the boiling point of water,i,e. the temperature of water. So quantity of salt is an independent variable while the temperature of water is dependent variable, when other factors are kept constant.
if I assume that you are talking about the salt: Sodium Chloride; it's effect on the boiling point of water is that the boiling temperature would be raised but to such small amount that it is difficult to notice without a scientific thermometer. So; no it doesn't.
The boiling point of salt is much much higher than the boiling point of water. So the salt stays behind while the temperature of the water remains at the boiling point of water.
it decreases the surface tension of the water.
By adding salt it means that you are adding an impurity into the water. Impurities can lower the boiling point, while increasing its melting point.
What did you observe! This is not a question we can answer as we were not present when the salt was added.
Yes, Salt also lowers the freezing point of water, and lowers the boiling point of water. Add salt to a boiling pot of water and it immediately boils faster/harder at the location that the Salt hit the water.
Adding salt to the water makes the egg easier to peel.
The quantity of salt added to water is under your control and it will change the boiling point of water,i,e. the temperature of water. So quantity of salt is an independent variable while the temperature of water is dependent variable, when other factors are kept constant.
Salt
Actually, it's when salt is added; it decreases the boiling point of water.
If your question means: If salt is added to water will it take longer to boil using the same conditions to boil fresh water? Adding salt elevates the boiling point of water so the mass of water has to be heated to a higher temperature to boil, therefore, boiling time is increased.
Don't add salt. Salt raises the boiling point of water, making it take longer.
Salt water, but the water will stop boiling because upon adding the salt it raised the boiling point of water.
It is a physical change because when salt is added to water,it is dissolved in it which only changes its physical appearance.
Adding salt increases the boilling point of the water, thus decreasing cooking time.