The Atom (Simplified) - Video Tutorials & Practice Problems

The Atom (Simplified) Concept 1

the atom represents the smallest part of an element and is the basic fundamental unit in chemistry. Now it is comprised of four major parts. The first part is the nucleus. It serves as the center of an atom that possesses two subatomic particles of neutrons and protons. Here we have an image of the atom below. We're going to say here that this orange band represents the nucleus inside of it. We have these red and blue balls which represent our neutrons and protons, respectively. Now the neutrons. These are the subatomic particles that carry no charge and are found within the nucleus. The protons are the subatomic particles that carry a positive charge and are also found within the nucleus. Outside of the nucleus. We have our electrons, the electrons are the subatomic particles that carry a negative charge and they spin around the nucleus. So these electrons here are rotating around the nucleus itself. Now, what you need to realize here is that this image of the atom is not drawn to scale the electron cloud, which is where we find the electrons is about 1000 or actually 1000, 1 million times larger than the nucleus. So in actuality the nucleus would be this little dot and the atom would be this entire thing. The nucleus would be incredibly incredibly small when compared to the entire volume of the atom itself. So just keep that in mind. Although the nucleus contains two subatomic particles in itself is very, very small.

The Atom (Simplified) Example 1

So if we take a look at this example question, it says which of the following statements is true First, a. Protons and electrons have charges of the same magnitude, but opposite science. Well, we said that protons are positively charged and electrons are negatively charged, so they definitely have opposite science. We could think of a proton as having a plus one charge and an electron having a minus one charge. So their magnitudes basically the number assigned with the charge. They're the same there, One right plus one minus one. So the first statement is true. Now let's see why the other statements are not true. Here are the number of protons must equal the number of neutrons within the atom. All right, so if we look up above, we said that we had five of these protons within the nucleus and we had six of these neutrons within the nucleus. In this example of the atom, we can clearly see that the number of protons and neutrons are not equal Now. They're gonna be times when Ah, certain Adam may have the same number of protons and neutrons, but that's not always a given. So this statement is not always true. The atom is best described as a uniforms, fear of mass in which electrons are embedded. All right, So if we look at the atom itself, Um, first of all, I said that the nucleus, I blew it up to show what's within it. But in reality, the nucleus is extremely small when it comes to the atom. Okay, it's very, very small in relation to the whole volume of the atom. We're also going to say here that the word uniforms is what gives this away is being wrong. The atom isn't uniformity is not the same throughout there is a part of the atom. That's the nucleus, which is different from other parts of the atom, which are not the nucleus within the atom we have swirling around the nucleus. These electrons Okay, so the composition is not exactly the same everywhere. There's unique parts to the atom in different places. So this would mean that it's not a uniforms, fear of matter. It has different parts to it. The volume of the nucleus is very large fraction of the total volume of the atom. So this is saying the exact opposite of what I said, the nucleus itself is extremely small in the image above. I've blown it up to show it better to show that within the nucleus are housed our protons and neutrons. In reality, it be super, super small and hard to see all these protons and neutrons. So this is false. It's very small fraction of the total vine of the atom. Now that we've done this example question, let's continue onward without discussion of the nucleus of the atom.

The Atom (Simplified) Concept 2

So we've talked about the nucleus. It's at the very center of the atom. It's extremely small in relation to the total volume of the atom, and it contains protons and neutrons. Now, when it comes to our nucleus, there are forces at work that helped to keep the nucleus together. But there's also forces at work. They try to pull it apart. Now we're gonna say, within the nucleus, there are these two major forces that characterized the behavior between protons and neutrons. Now we have what's called our nuclear force. The force within the nucleus that pulls together protons and neutrons. The way we have to think about it is in chemistry. We say that opposites attract. If you have opposite charges, you attract one another. Same charges repel one another. If you think about it, you have positively charged protons around. If you get them close enough to each other because they have the same charge, they're gonna want to repel each other. The way we prevent this from happening is the neutrons. The neutrons have no charge for a reason. They kind of act as the glue that keeps the nucleus together. Okay, we'll go into greater detail several chapters from now, when we cover nuclear chemistry and talk more in depth about nuclear force and electrostatic force. But just realize here that the neutrons kind of act as the glue that keeps together the protons, which have the same charge. All these protons with positive charges don't want to be next to each other now. Besides the nuclear force, we have the electrostatic force. Theological static force is the force within the nucleus that pulls apart protons and neutrons. So it's just basically this balancing act between the two forces. If nuclear forces greater than electrostatic force, it has an effect on the nucleus. If electrostatic force is greater, the nuclear force, it has an effect on the nucleus. Now we're going to say, for a stable nucleus that is held together, remember the forces holding it together is the nuclear force. It keeps them. It keeps everything together. The electrostatic forces was trying to pull things apart. If you wanna have a stable nucleus that is together, you want to make sure that your nuclear force is greater greater than your electrostatic force. So just realize again. The four primary parts of the atom and realize that within the nucleus, it's not a done deal that it's going to hold together and your animal exist. You have these two forces that are kind of like odds with one another, and if one is greater than the other, it can either mean the nucleus is held together or it's broken down and totally destroyed. Now that we've understood the basic parts of the atom, now that we discussed the nucleus, let's continue onward to our next question.

The Atom (Simplified) Example 2

So if we take a look at this example question, it says which the following statements is false. So we're looking to see what is not true. A. The nucleus is composed of protons and neutrons. Well, we know that's true. We've talked about that in the very beginning. The the nucleus has protons and neutrons, and spinning around the nucleus are the electrons. So this is true when the nuclear force is less than the electrostatic force than the nucleus will not remain intact. All right, so let's go up above. We said that the nuclear force hold it together. The electrostatic force tries to pull it apart. We said that the nucleus will be held together as long as the nuclear force is greater than the electrostatic force. But what happens if that's not true? Well, if your nuclear forces less than your electrostatic force, it makes sense that the nucleus would not be held together. So this is also true, right? Because we're saying the opposite of what we set up here. The nucleus has an overall neutral charge. Well, the nucleus houses what positive protons and neutral neutrons. So I'm just doing shorthand. Proton P has a positive charge Neutrons and has no charge. Usually we denote that with a zero or circle here to show that it has no charge. Think about it. We have positive charges on Lee within the nucleus. There is no other charges within it. So the nucleus overall should have a positive charge, not a neutral charge. So this is false. And then d when the nuclear forces greater than the electrostatic force, then the nucleus will remain intact. Well, that's exactly what we set up above. If your nuclear forces greater than your electrostatic force, then the nucleus is stable and will be held together. So just remember, when it comes to the nucleus, we have these two forces that air opposing one another trying to be the primary force. And this can either lead to the stability of the nucleus or have it fall apart.