Month: July 2016

Actinides

Actinides

Actinides

07/31/16

“What are the actinide elements?”

As we continue throughout our tour of the periodic table, we approach a most virulent group of chemicals known as the actinides. All of the actinides have relatively high density, plasticity, and level of radioactivity. The elements that make up the actinide metals include actinium [Ac], thorium [Th], protactinium [Pr], uranium [U], neptunium [Np], plutonium [Pu], americium [Am], curium [Cu], berkelium [Bk], einsteinium [Es], Fermium [Fm], Mendelevium [Md], nobelium [No], and lawrencium [Lr]

Lanthanides

Lanthanides

Lanthanides

07/30/16

“What are the lanthanide metals?”

Continuing on with our tour of the periodic table, we have come across a series of metals with atomic numbers 58 through 71 called the lanthanides. The lanthanides are bright, silvery, and are so soft that they could be cut with a knife. Lanthanides react with hot water to produce hydrogen gas. Lanthanides used to be called the rare metals, not because they were rare, but because it is very difficult to find the in their pure form. The elements that make up the Lanthanides include lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), and lutetium (Lu).

Reversable reactions

Reversable reactions

Reversible reactions

07/24/16

“Is it possible for atoms to revert to their original state after a chemical reaction?”

 

As we all know, when a series of elements undergo a chemical reaction, the elements and their composition will change as a result. However, is it possible for the products to reverse this change and revert to their original forms? Believe it or not, this is a common process. Products of a reaction can re-react and reform into the reactants! This phenomena is known as a reversible reaction, and the symbol for this process is shown in the picture.

Noble gases

Noble gases

Noble gases

07/28/16

“Are there any elements out their that are nearly completely non-reactive?”

We are about to approach probably one of the most interesting parts of the periodic table, the small but important group known as the noble gases. The nobles gases are very special for one very peculiar fact about them: their outer valence shell is completely filled! This makes them chemically inert, which gives them an extremely nonreactive nature with other elements. Noble gases are called noble gasses because in addition to being  colorless, tasteless, odorless, and non-flammable, they also have a low melting and boiling point, which causes them to be gases at room temperature. The elements that make up the noble gases include helium [He], neon [Ne], argon [Ar], krypton [Kr], and xenon [Xe].

Halogens

Halogens

Halogens

07/27/16

“What does the halogen group do?”

During our tour of the periodic table we encounter a very interesting group in the column XVII called the halogens. When the halogens react with water, they form very strong acidic compounds that can made into salts. Halogens usually have an oxidation number of -1, which makes them some of the most reactive elements in science. In fact, halogens are so reactive that directly ingesting some of them can be fatal to the human body!. The elements that make up the halogens include fluorine [F], chlorine [Cl], bromine [Br], Iodine [I], and astatine [At].

Non-metals

Non-metals

Non-metals

07/26/16

“What are some of the properties of non-metals?”

After reviewing the different type of metals and metalloids, you might be wondering, “What are some of the objects that are not metals at all, what are their properties?. Well, when one thinks about it logically, if metals have one type of behavior, then it would not be too far fetched for the opposite type of material to have opposite properties? This is in fact the case with non-metals. Nonmetals in groups 12-14 in the periodic table. Non-metals do not conduct heat or electricity very well, and are very brittle. Non-metals usually have oxidation numbers of +/-4, -3, and -2 as a result of being on the far-right side of the periodic table. The elements that make up the non-metal category include hydrogen [H], carbon [C], nitrogen [N], oxygen [O], phosphorus [P], sulfur [S], and selenium [S]

Metalloids

Metalloids

Metalloids

07/25/16

“What’s a metalloid?”

When browsing through the periodic table, you might see a group of elements that have a very strange description called metalloids. In short, metalloids are elements that have properties of both metals and non-metals. The elements that make up the metalloid group include boron [B], Silicon [Si], Germanium [Ge], Arsenic [As], Antimony [Sb], Tellurium [Te], Polonium [Po], and Astatine [At]. These elements are typically very brittle and have a fair amount of electrical conductivity. What makes metalloids especially interesting is that some of them (such as Germanium and silicon) have the properties of being semiconductors.

Post transition metals

Post transition metals

Post transition metals

07/24/16

“What properties do the non-transition metals on the periodic table have?”

We are about to enter one of the most controversial parts of the periodic table. What happens with the group of elements in between the transition metals and the metaloids? Well, let’s think about it for a moment. These elements typically have higher electronegativities and lower melting points, as well as a softer structure. Examples of metals in this group include aluminum [Al], gallium [Ga], lead [Pb], tin [Sn], thallium [Tl], and Indium [In]. Occasionally the group 12 metals are also included in this classification.

Transition metals

Transition metals

Transition metals

07/23/16

“What properties do those metals in the middle of the periodic table have?”

Something very interesting happens with the elements in the middle of the periodic table. The 38 metals from groups 3-12 have valence electrons present in more than one shell. This makes them able to have more than one oxidation state, or that they have different ionic forms (which is why we must use roman numeral for their naming scheme). Some of the metals in this group include copper [cu], manganese[Mg], and zinc [Zn]