What is the difference between an a particle and a helium atom?

Video transcript

welcome back everyone. What is the notation for the alpha particle? And we have choices A through D. To consider. We're going to begin by recalling that an alpha particle is repelled bye, positive electrodes. And due to this repulsion alpha particles recall consist of two protons and two neutrons. So looking at our answer choices, we see that in choice A. We have helium with In the left hand superscript a mass number of four. And then in the left hand subscript a atomic number of two, recall that atomic number tells us our number of protons. So we can confirm that we have two protons. However, our mass number being four tells us that we would likely also have two neutrons. So this does check out. However, we see that helium is neutral. And if we know that alpha particles are repelled by positive electrodes, we would need to see a charge on this helium atom. So we would go ahead and rule out choice A. Because it's neutral. Moving on to example B. We can automatically also rule this out because we see the mass number is zero. And we can also see that we have E. As our particle and E we want to recall is representative of a beta particle. So whenever we have a beta particle with a mass number of zero and an atomic number of negative one, we know that this is a beta particle. We're looking for an alpha particle. So let's rule out example B or sorry choice be moving on to toy. See we have helium. Now with a plus to charge a mass number of four and an atomic number of two. We can confirm that because of this. Plus two charge and as well as the mass number being four, telling us that we have two protons from again, the atomic number of two here, and therefore two neutrons due to that mass number of four. We can confirm that this would definitely represent an alpha particle. And so we can confirm that choice C. Is definitely a correct choice. And now looking at choice D, we can see that we have E with a mass number of zero and an atomic number of one. And we should recall that this particle is considered a positron particle. And so we would rule out choice D. Meaning that the only correct notation for an alpha particle is choice. See where we have helium with a plus to charge a mass number of four and an atomic number of two. I hope that everything I went through is clear. If you have any questions, please leave them down below and I'll see everyone in the next practice video