UCSB Science Line
Sponge Spicules Nerve Cells Galaxy Abalone Shell Nickel Succinate X-ray Lens Lupine
UCSB Science Line
How it Works
Ask a Question
Search Topics
Our Scientists
Science Links
Contact Information
Does salt dissolve quicker in room temperature than in cold water?
Question Date: 2017-10-22
Answer 1:

Dissolving is a process where solvent molecules surround other molecules, which causes the solid to become uniformly dispersed in a solution. In your example, salt ions in a solid are slowly surrounded by water molecules. This happens through the collision of molecules, where solvent molecules collide with salt ions in the solid, and slowly eat away at the block of solid.

If you increase the temperature, molecules vibrate more quickly, so you would expect these collisions would happen more quickly, and any dissolution would also happen more quickly. Also, depending how you are heating your solution, you may also establish convection currents in your solution, which would also speed up dissolution.

All other things being equal, you would normally expect a hotter solution to dissolve things more quickly. However, this doesn't tell you about how much can be dissolved, which will depend on the material. Some things, like sugar, or sodium chloride (table salt) are more soluble at higher temperature. This means you can put more salt or sugar in water when the temperature is high, but not all things behave in this way!

Answer 2:

The best way to answer this is to try it yourself!

Take 3 glasses of water. Add cold water to one (either ice water, or water from the fridge), add room temperature water to the second, and add hot water to the third. Then, add 1 teaspoon of salt to each glass at the same time, and time how long it takes each to dissolve.

I think you will find out that the salt dissolves quickly in the hot water, more slowly in the room temperature water, and slowest in the cold water. In fact, the salt might never even fully dissolve in the cold water!

It out that this trend is true for dissolving pretty much anything into water– salt, sugar, baking soda, etc. The hotter the water, the faster you can dissolve something in it.

Answer 3:

The kind of salt we eat dissolve more quickly in room temperature water than in cold water. That is because at room temperature, the tiny particles that make up the water and salt move around and vibrate at higher speeds. This mixes the salt and water faster and makes the salt dissolve faster. In general, mixing makes things dissolve faster, and that's why we stir our tea or coffee when we add sugar and cream.

Answer 4:

That's an experiment you can do:
Put a half teaspoon of salt in cold water and a half teaspoon of salt in room temperature water in 2 glasses with the same amount of water, and stir one of them with each hand. Does the salt dissolve faster in 1 glass? Does all the salt dissolve, in both glasses?

Salts are usually more soluble in hotter water - that means that more salt will dissolve in hotter water, but that doesn't answer your question about whether the salt will dissolve FASTER. Maybe I'll do the experiment!

Ordinary table salt- sodium chloride - is unusual, because the amount of salt that dissolves in colder and hotter water is almost the same. I'm surprised, and I just found a scientific article that tells about this. I'm going to read it now! Thank you for your question!

Answer 5:

Salts dissolve quicker in hot water compared to cold water (of course, assuming the same amount of enough water to dissolve salts). The reason is indicated in the temperature itself.

High temperature means higher average velocity of water molecules, thus higher kinematic energies to break the bonds of salts (dissolving salts). Another reason is the higher chance for hotter water molecules to interact with salts, and it is another reason that salts dissolve quicker in hot water. In short, the reasons are: higher velocities, higher energies and more frequent interactions.


Answer 6:

Salt dissolves better in warmer water than in colder water. This is because the water molecules are moving faster and can keep the salt ions from joining together by pulling on them.

Answer 7:

Yes, salt and other ionic compounds like it will dissolve faster the hotter the water it is dissolved in. This is because hot temperatures make atoms move quicker and the quicker they move, the easier they come apart! You can try this experiment at home if you want!

Answer 8:

Yes! Salt does dissolve quicker in room temperature water than in cold water. In fact, you can take that even further, and say that any solid substance that can dissolve in water, will dissolve quicker in hot water than room temperature water. Every substance (sugar, salt, baking soda) will dissolve differently in water, and each one will have a different maximum weight that can dissolve in a given amount of water. When you hit the maximum amount that will dissolve, you say the mixture is a saturated solution at room temperature. For every temperature of water, there is a different maximum amount (generally more) of substance that will dissolve.

You can also look up what a "super-saturated solution" is, and see how getting water super hot can cooling it down actually change this maximum amount that can be dissolved at room temperature.

Answer 9:

You are correct, salt dissolves quicker in room temperature than in cold water. Salt is made of two atoms (sodium and chlorine). Salt dissolves because water molecules separate these two atoms. Higher temperatures mean the particles move faster, making the separation quicker.

Click Here to return to the search form.

University of California, Santa Barbara Materials Research Laboratory National Science Foundation
This program is co-sponsored by the National Science Foundation and UCSB School-University Partnerships
Copyright © 2020 The Regents of the University of California,
All Rights Reserved.
UCSB Terms of Use