Why do atomic radii decrease from left to right across a period of the periodic table?

Video transcript

Hello everyone today we are being given the falling problem, which explains why atomic radius increases as you go down a group in the periodic table. So you have the following four answer choices. So we know that atomic radius. The atomic radius is a radius decreases from left to right. So as you go from the left side of the periodic table to the right side, our radius decreases. And so this decrease of a radius is going to result. We'll make that an equal sign. To avoid confusion. This will result in an increase in our effective charge or effective nuclear charge. And so that effective nuclear charge is essentially responsible for pulling the electron cloud. So it pulls the electrons closer. And so as you put as you have these electrons around an orbital around a nucleus and you increase the effective nuclear charge of these of the nucleus, you're going to essentially exert a greater force on the electrons surrounding it and pull those electrons closer to you. And as a result this is going to decrease that radius. And so we can also say that atomic radius increases down a group. So as you go from the top of the periodic table to the bottom of the periodic table, the atomic radius is going to increase. And so what does this mean? This means that the number of our energy levels increase. So the number of our energy levels increase. And so as you increase your number of energy levels or the number of orbital's that you have, you're going to subsequently increase the distance between the nucleus and the most were the outermost orbital. And so which one of these answer choices aligns with that ideology That's going to be answer choice. A atomic radius increases down a group because of increasing energy levels from the nucleus. And so with that we've answered our question overall, I hope that this helped, and until next time.