|Does salt dissolve quicker in room temperature
than in cold water?
|Question Date: 2017-10-22
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!
The best way to answer this is to try it
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.
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.
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!
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.
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.
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!
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
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
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
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