Separating rock salt
Summary
TLDRThe video demonstrates how to separate salt from sand in a rock salt mixture. First, the rock salt is crushed to break down large salt crystals. Next, the mixture is stirred in water, allowing the salt to dissolve while the sand remains insoluble. The solution is then filtered, leaving the sand behind. Finally, the salt solution is evaporated by heating, causing the water to evaporate and leaving behind salt crystals. The experiment successfully separates the salt from the sand using basic laboratory techniques such as filtration and evaporation.
Takeaways
- 🔨 The experiment involves separating salt from sand in a mixture of rock salt.
- 🧂 Rock salt is a mixture of salt and sand, used on roads in winter to melt ice and improve grip.
- 🧹 Step 1: Crush the rock salt with a mortar and pestle to break down large salt crystals, making them easier to dissolve.
- 💧 Step 2: Add the crushed rock salt to water and stir to dissolve the salt while leaving the sand undissolved.
- 🌡️ The sand is insoluble, so it settles at the bottom of the beaker, while the salt dissolves in the water.
- 🧪 Step 3: Filter the mixture using filter paper to separate the sand from the salt solution.
- 🔍 After filtering, the sand remains in the filter paper, and a salt solution is collected in the beaker.
- 🔥 Step 4: Use evaporation to separate the dissolved salt from the water by heating the solution in an evaporating basin.
- ⏳ As the water evaporates, salt crystals begin to form in the evaporating dish.
- 🎯 The experiment successfully separates the sand and salt, leaving sand in the filter paper and salt crystals in the evaporating dish.
Q & A
What is rock salt and what is it used for?
-Rock salt is a mixture of salt and sand, used to melt ice on roads in winter and improve traction, making it less likely for cars to crash.
Why is the rock salt mixture crushed with a mortar and pestle?
-The rock salt mixture is crushed to break down large salt crystals into smaller ones, which helps them dissolve more easily in the next step.
What happens when the crushed rock salt is added to water?
-When the crushed rock salt is added to water, the salt dissolves, but the sand, which is insoluble, settles at the bottom of the beaker.
What is the purpose of stirring the rock salt mixture in water?
-Stirring the mixture helps the salt dissolve more completely, leaving the sand undissolved at the bottom of the beaker.
How is the sand separated from the salt solution?
-The sand is separated from the salt solution by filtering the mixture through filter paper. The sand stays in the filter paper, while the dissolved salt passes through.
Why is evaporation used in the final step of the experiment?
-Evaporation is used to separate the dissolved salt from the water, leaving behind dry salt crystals once the water evaporates.
Why is only a small amount of salt solution used in the evaporating basin?
-A small amount, about 10 milliliters, is used so that the water evaporates quickly, speeding up the process.
What is the role of the Bunsen burner in the evaporation step?
-The Bunsen burner heats the salt solution in the evaporating basin, causing the water to evaporate and leaving behind the salt crystals.
How do you know when to stop heating the solution in the evaporation process?
-Heating is stopped when salt crystals begin to form in the evaporating basin, indicating that the water is almost fully evaporated.
What are the final products after completing the experiment?
-The final products are dry salt crystals in the evaporating basin and sand collected in the filter paper, successfully separated from each other.
Outlines
🧂 Introduction to Rock Salt and Its Use
The presenter introduces rock salt, a mixture of salt and sand, explaining its practical use in winter to melt ice and improve road grip, reducing the risk of accidents. The experiment aims to separate the salt from the sand in a rock salt mixture.
🔨 Crushing Rock Salt with a Mortar and Pestle
The presenter explains the first step of the experiment, which involves placing rock salt in a mortar and crushing it with a pestle. The goal is to reduce the size of the salt crystals, making them smaller so they can dissolve more easily in the next stage.
💧 Dissolving the Salt in Water
The crushed rock salt is added to a beaker of water, and a stirring rod is used to dissolve the salt. The presenter notes that while the salt dissolves, the sand remains insoluble and settles at the bottom of the beaker.
🧪 Filtering the Mixture to Separate Sand
In the next step, the mixture is filtered using a funnel and filter paper. The goal is to separate the insoluble sand from the salt solution, as the sand is too large to pass through the tiny pores in the filter paper, leaving the dissolved salt in the beaker.
🔥 Evaporating the Water to Obtain Salt Crystals
The salt solution is transferred to an evaporating basin, and about 10 milliliters is heated to evaporate the water. The presenter uses a Bunsen burner, explaining that a small volume speeds up evaporation, and salt crystals start to form as the water evaporates.
🎉 Final Separation: Salt and Sand Successfully Isolated
The presenter concludes the experiment, showing the successful separation of salt and sand. The salt has crystallized in the evaporating basin, and the sand is left in the filter paper, completing the process of separating rock salt.
Mindmap
Keywords
💡Rock salt
💡Mortar and pestle
💡Dissolving
💡Insoluble
💡Filtration
💡Filter paper
💡Evaporation
💡Bunsen burner
💡Crystals
💡Separation
Highlights
Rock salt is a mixture of salt and sand used to melt ice on roads in winter and improve grip.
The experiment aims to separate the salt from the sand in a rock salt mixture.
Step one involves crushing the rock salt using a mortar and pestle to break the salt crystals into smaller pieces.
Crushing the salt crystals helps them dissolve more easily in water during the next step.
In step two, the crushed rock salt mixture is added to a beaker of water and stirred to dissolve the salt.
Salt dissolves in water, while sand is insoluble and remains at the bottom of the beaker.
Step three involves filtering the mixture to separate the insoluble sand from the salt solution.
The filter paper captures the sand particles, allowing the salt solution to pass through.
After filtering, the sand is left behind in the filter, and the salt remains dissolved in the water.
Evaporation is used to recover the salt by heating the salt solution and allowing the water to evaporate.
Only a small volume of salt solution (10 milliliters) is used for faster evaporation.
The solution is heated in an evaporating basin, and as the water evaporates, salt crystals begin to form.
The experiment is complete when the water has evaporated, leaving behind dry salt crystals.
The separation process successfully isolates the sand in the filter and the salt as crystals after evaporation.
This experiment demonstrates the process of separating mixtures through filtration and evaporation techniques.
Transcripts
so what i've got here is something
called rock salt
and rock salt is actually a mixture of
salt
and sand and it's used to put on the
roads in winter
because it melts the ice on the road and
improves the grip makes it less likely
that cars will crash
in this experiment what i'm going to do
is i'm going to separate the salt
from the sand in the mixture of roxol
now my first step is what i'm going to
do is get a
mortar and a pestle i'm going to place
some of the rock salt
into the mortar and i'm going to crush
it and the reason that i'm going to do
this
is so make sure that the crystals of
salt which are quite big at the moment
are going to be really small i'm going
to break down those crystals make them
small crystals
and that will help them dissolve in the
next stage
step two is that i want to take some of
my crushed
rock salt mixture put some of it into a
beaker of water
in fact let's put all of it in and using
a stirring rod
i'm going to stir the mixture and the
reason i'm going to stir it
is so all of the salt dissolves
so i've given that a good stir and all
of the salt has now dissolved
the sand is insoluble so it hasn't
dissolved so i don't if you can see
but at the bottom of that beaker there
is the insoluble
sand now step three
is i'm going to filter that mixture
so we need a beaker and a funnel
and a piece of filter paper folded into
a cone
so i'm now going to pour my dissolved
rock salt mixture
through my filter paper and the aim of
this
is to remove the sand from the solution
because the sand
grains are going to be too big to fit
through the pores the tiny little holes
in the filter paper the salt
because it's dissolved in the solution
will go through those pores so what i'm
going to get in the bottom of my beaker
is a solution of salt
but all the sand should stay in the
filter paper
so the mix just now finished filtering
and you can see we've got the bottom of
the beaker we've got some
some salt solution and in the filter
you can see that all the sand has been
caught so we've now successfully removed
the sand from our solution
and the salt is now dissolved in that
water there
now i don't want that salt to stay
dissolved in the water because i want
dry salt so the next thing i'm going to
do
is some evaporation and as we saw
earlier evaporation is a technique you
use when you want to separate a liquid
from a soluble substance so salt is a
soluble substance dissolved in
the water so hence
evaporation is the suitable technique
here so i'm going to take about 10
milliliters
of my salt solution
and place it into an evaporating basin
and the reason i only want to use about
10 milliliters is because if i used more
than that it would take
quite a long time for the water to
evaporate so i'm just going to use a
small volume just 10 milliliters
so my solution evaporates quick
so because we're doing evaporation i
then need to heat my
evaporating basin containing
the solution
and the purpose of that is to for the
water to evaporate
so i've just turned off the bunsen
burner when the crystals began to form
inside the
dish i'm just going to allow those
crystals to continue forming there
so heating the solution has evaporated
the water
leaving the salt crystals behind
so there's the sand in the filter
and there's the salt crystals still in
the evaporating basin
so i've been successful i've separated
the salt
from the sand from the rock salt
تصفح المزيد من مقاطع الفيديو ذات الصلة
5.0 / 5 (0 votes)