Group 4A Elements Definition Properties Video Lesson Transcript
Group 4A Elements
Sure, every group of elements is important. I mean, where would we be without the noble gases. There would be no neon signs and no helium balloons. Or what if the alkaline earth metals disappeared? There would be no more calcium for your bones. Or what about the halogens? No more chlorine for the swimming pool. But I'd wager group 4A is the most important group of elements. Sure, you'd miss your bones, the helium balloons, the neon signs, and the swimming pools, but you'd really miss group 4A!
Okay, okay, all of the groups are important, and I don't want to play favorites, but some of the elements in group 4A are extremely important to you - and you might not even know it! Group 4A consists of Carbon (C), Silicon (Si), Germanium (Ge), Tin (Sn), and Lead (Pb) and is located on the middle-right of the periodic table. All of these elements are solids at room temperature.
Before we delve into the details of these important elements, let's get some terminology straight. Depending on the periodic table or textbook you're looking at, these elements can go by different names. You already know they can be called group 4A, but they can also be referred to as group 14 or group IVA. All mean the same thing.
Properties of Group 4A Elements
Although you might not think carbon has a lot in common with tin, they're placed in the same group since they have similar properties. Let's take a moment to look at all of the properties they share.
All elements in this group have four valence electrons. These are the outermost electrons, farthest away from the center of the atom, that determine some of the element's properties. They also typically have low electronegativities, which means they don't want another element's electrons. There are some groups of elements that really want to take electrons from other elements, but not group 4A.
All elements in this group tend to lose their valence electrons. If an element in 4A loses all four valence electrons it gets a +4 charge, also known as a +4 oxidation state. Generally, the elements at the top of this group have the +4 oxidation state while the elements at the bottom have the +2 state, but we'll take a closer look at this when we examine each element. On occasion, a group 4A element will have an oxidation state different than +4 or +2, such as -4. This oxidation state means that no electrons were lost and four were gained from another element.
When an atom has a positive charge, like +2 or +4, it is known as a cation. When it gets a negative charge, like -4, it is known as an anion. In order to keep the words cation and anion straight, I always think of a cute cat for cation, which is positive, just like a cation's charge.
As you go down the periodic table, group 4A elements become more metallic, meaning they can be good conductors of heat and electricity, they are malleable (or bendy), and they have a metallic luster. Finally, most form covalent bonds, or when electrons are shared between atoms.
Now, into the good stuff. Why are these elements so important?
Let's start with carbon, which is the sixth most-abundant element in the universe. In fact, carbon can be found in so many places, it even gets its own branch of chemistry called organic chemistry. Carbon forms the building blocks for everything that is living, so you are a carbon-based life form! Like most of the group 4A elements, carbon forms covalent bonds, meaning it shares its electrons with another element. On rare occasions it can form ionic bonds, meaning valence electrons are transferred from one atom to another atom.