Understanding Electron Trends in the Periodic Table

As one moves from left to right across a period in the periodic table, what occurs?

• A. The atomic mass decreases
• B. The number of neutrons increases
• C. The number of electrons increases by one
• D. The number of protons decreases

Answer: (C)

As one moves from left to right across a period in the periodic table, elements gain protons and electrons. Each subsequent element in a period has one more proton in its nucleus than the element before it, which is reflected in the increasing atomic number. For example, moving from sodium (Na) to magnesium (Mg), sodium has 11 protons, while magnesium has 12. Consequently, as protons increase, electrons also increase to maintain electrical neutrality, resulting in an increase of one electron for each step across a period. Therefore, moving from left to right, the primary observable trend is the increase in the number of electrons by one for each successive element. This fundamental characteristic is key to understanding the periodic properties and behavior of elements.

As you prepare for the Kaplan Nursing Entrance Exam, it's essential to grasp not just the nursing concepts but also foundational scientific principles like those laid out in the periodic table. So, let's talk about one major trend that you'll encounter as you traverse from left to right: the fascinating increase in the number of electrons.

You see, in chemistry, the periodic table isn't just a grid of elements; it's a treasure trove of trends and patterns. One of those patterns is all about electrons. If you roll along a period— say, from sodium (Na) to magnesium (Mg)—you'll notice that each step brings in more electrons. Sodium has 11 protons and, consequently, 11 electrons, while magnesium bumps things up with 12 protons and 12 electrons. It's pretty neat, right?

Now, you might wonder, "Why does this matter for nursing?" Well, understanding electron arrangements can help illuminate some key concepts in pharmacology and biochemistry, which are crucial when you’re dealing with patient care. The way ions behave—charged particles formed when electrons are gained or lost—underpins how medications interact in the body. Isn't it wild how something seemingly abstract can have real-world applications?

So, as you navigate through elements, keep in mind that as you move across, the atomic number, which represents the number of protons, climbs one by one. And guess what? That means the number of electrons rises correspondingly. Just one additional electron per subsequent element. It's that simple.

Let's break that down more: Imagine you are gathering pets—one at a time, right? You start with a cat (Na, with 11), and when you decide to adopt another (Mg), you now have one more! But here’s where it gets a tad complicated. While neutrons can vary—thus leading to different isotopes—the steady flow is always with electrons and protons increasing together. So, if someone asks what happens as you stride across the periodic table, you now have a solid answer: with each new element comes one more electron!

But hang on; do remember that while electrons are cute little characters in this story, they’re deeply connected to the protons’ stronghold in the nucleus. In essence, protons pull electrons in, creating that balance we all talk about in chemistry—stability, neutrality, and all that jazz.

So here's the thought: why not use this knowledge as a stepping stone? When you're reviewing your materials for the Kaplan Nursing Entrance Exam, keep the periodic table in mind, and think about the interplay of these particles. It can help you better understand everything from the molecular structure of drugs you’ll administer to how the human body absorbs these compounds.

In summary, as you move from left to right across the periodic table, embrace the increasing complexity of elements. With each step, you bolster your understanding of essential scientific principles that weave into the tapestry of nursing itself.

Let’s keep the momentum going, shall we? The journey through science isn't just about memorization; it's about connection—bridging the gap between pure theory and everyday practice in nursing.