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What is soap?
Why does soap work to get the grease and dirt off of dirty pans and other things when water alone can't do the job? Created by MIT+K12.
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how can you tell when something is polar or nonpolar?(28 votes)
I suppose you could take a known polar (or non-polar) liquid, such as water, and mix it with that 'something'. If they mix, it is polar (or non-polar, depending on the substance), and vice versa.(19 votes)
Nice! I've seen a soap with pH 5.5. Its apparently good for the skin. Why is this and what is mixed with the soap to convert it from base to acid?(10 votes)
The theory at least is that PH 5.5 is the natural PH of the skin.
If that means that PH 5.5 soap is better then other soap is not so certain.(3 votes)
Can gaseous substances be polar /nonpolar(7 votes)
Yes. Helium(He), Neon(Ne), Krypton(Kr), Xenon(Xe), Hydrogen(H2), Nitrogen(N2), Oxygen(O2), Carbon Dioxide(CO2), Methane(CH4), and Ethylene(C2H4) are all non-polar. Steam (water), Sulfur Dioxide(SO2), and Hydrogen Sulfide(H2S) are all polar.(5 votes)
Is there other dirt or other grit that soap can't take care of?(6 votes)
Iron filings, being neither polar nor nonpolar, cannot be washed off with soap.(1 vote)
What are examples of substances that are neither nonpolar or polar?(5 votes)
Substances like metals aren't non-polar or polar. This is because the electrons are shared in a "sea" of electrons.(4 votes)
This is kind of a stupid question but i want people to answer this.
What is soap and how is it formed.
If you can, please put a thumbs up and answer my Question(4 votes)
Soap is a substance used with water for washing and cleaning, made of a compound of natural oils or fats with sodium hydroxide or another strong alkali, and typically having perfume and coloring added.
Today, soaps are made from fats and oils that react with lye (sodium hydroxide). Solid fats like coconut oil, palm oil, tallow (rendered beef fat), or lard (rendered pork fat), are used to form bars of soap that stay hard and resist dissolving in the water left in the soap dish.
Learn more at:
http://sci-toys.com/ingredients/soap.html(2 votes)
- Does soap kill germs? If so, how do they kill germs?(3 votes)
There are four types of germs: bacteria, viruses, fungi, and protozoa.
Antibacterial soap is designed to destroy bacteria. There is another type of soap (called "regular soap") that only washes away bacteria.
Scientists debate whether antibacterial soap works, because after you kill bacteria, there is always a mutation. Since the soap is designed to kill only that specific bacteria, the mutation multiplies and eventually makes the person sick. Both type of soaps are effective.
Hope that helps!(3 votes)
Why do we rinse with water after washing our hands with soap? Would it be a more efficient way of cleaning if we used soap and then wiped our hands without rinsing?(3 votes)- Because the soap doesn't destroy grime or grease. Instead it bonds to it, making it possible to remove with water. If, after washing, your hands are still soapy, then you probably have a little of whatever you were trying to wash off still on your hands.(1 vote)
- Can plasma, solids and gasses be classified as polar of non-polar?(2 votes)
Yes. Plasma is basically an ionic gas so if you were to get NaCl to its boiling point, since it is ionic it completely skips the gas phase and goes straight to plasma. Same thing would happen with metals if you did the same thing.
Nonpolar solids tend to be very densely packed, especially hydrocarbons. O2 in its solid state at a high enough pressure can form what is known as red oxygen(mainly because it looks red at that temperature and pressure) or O8 or uncommonly, octaoxygen. This makes the oxygen even more dense. Polar solids on the other hand tend to be less densely packed because of hydrogen bonds and other similar forces and are thus more likely to float in a liquid.
Gasses can be classified as polar or nonpolar depending on what they dissolve in. Now this is not true for all gases but is true for a lot of them. An example of where this would be false is CO2. Now why is it false? It is because there are still dipoles in the CO2 and thus each individual bond is polar even though the molecule isn't and it also in water naturally undergoes an acid-base reaction forming hydroxide and carbonic acid. This carbonic acid is very similar to the bicarbonate that occurs in your blood. These 2 factors make CO2 readily dissolve in water even though it is nonpolar.
O2 also dissolves in water but in this case since the atoms are not often in their charged state(where 1 oxygen atom is negative and the other is positive), it is almost completely nonpolar. Instead what makes it dissolve in water more readily than say ethane or octane is the fact that it is so small that water can easily induce a dipole on the O2 molecules.(2 votes)
- In3:20, I noticed that the butter actually did not fully dissolve, even though he said it did. Is this just because the butter was solid, or is there another reason?(2 votes)
If you stir it long enough, it will dissolve completely.(1 vote)
3:20Video transcript
- This is a video about soap. Soap is made by treating oils with a strong alkaline solution. The Babylonians already
knew how to make soap almost 5,000 years ago,
using ashes and plant oils. Today, we take soap for granted. Have you ever wondered, "What is soap?" What is special about
it, and how does it work? Let's find out. But why do we even need soap? That's obvious: to wash away dirt. But what is dirt, and why can't we just use water to wash it away? Well, that's a good question,
but to understand this first we need some basic chemistry. If you take a substance like colored salt and dissolve it in a
liquid, such as water, then that substance is called a solute, and the liquid is called a solvent, and the resulting mixture
is called a solution. Almost all substances fall
into one of two types: polar and nonpolar. Water is a polar solvent, and anything that dissolves in water is a polar solute. And many other substances, such as oil, are nonpolar solvents, and anything that dissolves in them is a nonpolar solute. The problem is, oil and
water just don't mix. No matter how much you stir. Polar solute can only
dissolve in a polar solvent, and a nonpolar solute can only dissolve in a nonpolar solvent. In other words, like dissolves like. Let's see what happens
when we try to dissolve a solute in an incorrect solvent type. For our polar solvent, I
can just use some water. For a good nonpolar solvent, we're gonna need some help from a chemist. We're going to use hexane. Hexane is a hydrocarbon
with six carbon atoms. It looks like water, but it is volatile, highly flammable, and
must be handled with care. You already saw what happened when we mixed colored salt with water. The salt dissolved in the water, because salt is a polar solute, and water is a polar solvent. Now we're going to repeat this experiment using different solutes and solvents. Now we're going to try using
hexane instead of water. Salt is a polar solute, but hexane is a nonpolar solvent. And as we expected, the salt does not dissolve in the hexane, and settles at the bottom of the beaker. And now we will try the same thing, but this time we will use
a common nonpolar solute that you often find on
your frying pan: butter. And as we suspected, the butter does not dissolve in water. And just like with the salt, we will also test our
nonpolar solute with hexane. And as we suspected, the butter does dissolve in the hexane. So, as we expected, when we tried to mix our
solutes and solvents, the salt only dissolves in water, and the butter only dissolves in hexane. Like dissolves like. So why can't we just wash
a dirty pan with hot water? You've probably already
guessed the answer. Most dirt is oil-based, like the grease on your frying pan, and the water rolls off the grease, literally like water off a duck's back. So this is where soap comes in to help us. Soap molecule has a long nonpolar tail, and a short polar head. The grease on your frying pan is nonpolar, so trying to wash it away
with water is ineffective. When we add soap to the grease, the nonpolar tail of the soap molecule attaches to the dirt,
forming a micellar bilayer. When we add water to the mix, the polar head of the soap molecule attaches to the water, but the soap acts like a bridge between
the water and the dirt, and the resulting mixture
is called an emulsion. And now we can easily wash the emulsion away with water. Looks pretty clean to me! So let's put it to the test. You think 5,000 years of technology can help us wash the dirt off this car? (fast techno music) Let's find out.