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shift Metals

groups with metalloids


Characteristics of group 17 the the periodic table.

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· determine halogens.

· define physical and chemical properties of halogens.

· perform some provides of halogens.


You’ve probably seen halogen lights choose the persons pictured here. Friend may even have halogen lights in your home. If girlfriend do, girlfriend may have actually noticed the they gain really hot and also give turn off a the majority of light for their size. A halogen light differs from a continual incandescent light pear in having a tiny amount the halogen gas within the bulb. The gas combines chemically through the metal in the filament, and this extend the life of the filament. It permits the lamp to obtain hotter and give off much more light than a continuous incandescent light without burning the end quickly. What is halogen gas, and whichelementsare halogens? In this article, you’ll uncover out.  

Meet the Halogens

Halogensare highly reactive nonmetallicelementsin team 17 that the regular table. As you can see in the periodic table presented in theFigurebelow, the halogens encompass theelementsfluorine (F), chlorine (Cl), bromine (Br), iodine (I), and astatine (At). All of them are fairly common on earth except because that astatine. Astatine is radioactive and also rapidly decays to other, more stable elements. As a result, it is among the the very least common aspects on Earth.


Q:Based top top their position in the periodic table indigenous theFigureabove, how countless valenceelectronsdo girlfriend think halogens have?

A:The variety of valenceelectronsstarts in ~ one for aspects in group 1. The then increases by one native left to right across each period (row) the the regular table for groups 1–2 and 13–18. Therefore, halogens have seven valence electrons.

Chemical properties of Halogens

The halogens are among the most reactive of all elements, although reactivity declines from the peak to the bottom of the halogen group. Since all halogens have seven valenceelectrons, they room “eager” to gain one more electron. Doing so provides them a full outerenergy level, which is the many stable plan of electrons. Halogens often incorporate with alkalimetalsin team 1 the the routine table. Alkali metals have just one valence electron, i m sorry they space equally “eager” come donate. Reactions including halogens, especially halogens near the optimal of the group, might be explosive. You deserve to see some examples in the video at the URL below. (Warning:Don’t try any of this reactions in ~ home!)


Physical nature of Halogens

The halogen group is rather diverse. That includes elements that take place in 3 differentstates the matterat roomtemperature. Fluorine and also chlorine aregases, bromine is a liquid, and iodine and astatine aresolids. Halogens likewise varyincolor, together you can see in theFigurebelow. Fluorine and also chlorine space green, bromine is red, and iodine and also astatine are almost black. Like other nonmetals, halogens can not conduct power orheat. Contrasted with many other elements, halogens have reasonably lowmeltingandboilingpoints. You deserve to watch a laboratory demonstration that the melting and also boiling clues of halogens at this URL:http://www.youtube.com/watch?v=yP0U5rGWqdg.


Uses of Halogens

Most halogens have actually a range of necessary uses. A couple of are explained in theTablebelow.

A couple of Uses that Halogens




Fluorine helps stop tooth decay, so the is added to toothpaste as the compound salt fluoride. You have the right to learn exactly how it protects this at this URL:http://www.animated-teeth.com/tooth_decay/t4_tooth_decay_fluoride.htm.


Chlorine is the energetic ingredient in family members bleach. It gets rid of stains from clothes. It can additionally be provided to disinfect countertops and also other surfaces.


Bromine is provided to purifywaterin swimming pools and hot tubs. It reacts v bacteria and other germs and renders castle harmless.


Iodine is included to alcohol and used as an antiseptic. The reacts v germs on cuts and also wounds. Tiny amounts the iodine are additionally needed for good health. In the U.S., iodine is included to table salt to prevent iodine deficiencies. Go the salt you use contain iodine?

Q:Can friend relate few of these offers of halogens come the properties of this elements?

A:The ability of halogens to kill germs and also bleach apparel relates come their highly reactive nature.


· Halogens are very reactive nonmetal facets in group 17 the the regular table.

· Halogens includesolids,liquids, andgasesat roomtemperature, and they vary incolor.

· Halogens are among the many reactive of every elements. They have seven valence electrons, so they are an extremely “eager” to obtain one electron to have a complete outerenergy level.

· Halogens have actually a range of important uses, together as avoiding tooth decay and killing germs.

Explore More

TheTablebelowgives themeltingandboilingpoints of halogens. Develop a graph v the data, and also then define in native the patterns that you see in her graph.

MeltingandBoilingPoints of Halogens


Melting allude (°C)

Boiling suggest (°C)

















1. What space halogens?

2. Why are halogens very reactive?

3. Explain the physics properties that halogens.

4. Why is chlorine added to swim poolwater?

Transition Metals

Characteristics of teams 3 - 12 the the periodic table.

· identify transitionmetals.

· perform properties of transitionmetals.

· define thelanthanides and also actinides.


What do every one of the objects pictured over have in common? every one of them are made completely or mainly of copper. Copper has an amazing selection of uses, including food preparation pots, pipes pipes, roofing tiles, jewelry,musical instruments, and electric wires. Copper is a good choice because that these and also many other objects due to the fact that of that is properties. It deserve to be created into wires and also flat sheets, it’s a great conductor ofheatand electricity, it’s hard and strong, and also it doesn’t corrode easily. In all these ways, copper is a typical shift metal.

What space TransitionMetals?

Transition metalsare all theelementsin teams 3–12 of the routine table. In the regular table pictured inFigurebelow, they are theelementsshaded yellow, pink, and also purple. The change metals make up around 60 percent that all well-known elements. In enhancement to copper (Cu), fine known examples of shift metals encompass iron (Fe), zinc (Zn), silver (Ag), and gold (Au) (Copper (Cu) is pictured in its various applications in the opening image). You can explore particular transition steels with the interactive periodic table at this URL:http://www.ptable.com/.


Q:Transition metals have been referred to as the most usual of all metals. What execute you think this means?

A:Unlike some other metals, change metals have the properties that define the metals class. Lock are excellent conductors of electricity, for example, and also they likewise have luster, malleability, and also ductility. You can read an ext about these properties of shift metals below.

Properties of change Metals

Transition steels are remarkable conductors ofheatas well together electricity. They room malleable, which method they have the right to be shaped into sheets, and also ductile, which way they deserve to be shaped into wires. They have highmeltingandboilingpoints, and also all aresolidsat roomtemperature, except for mercury (Hg), which is a liquid. Transition metals are additionally high in thickness and very hard. Many of them room white or silvery incolor, and they are normally lustrous, or shiny. Thecompoundsthat change metals form with otherelementsare often really colorful. You have the right to see several examples in theFigurebelow.


Some nature of transition metals set them apart from other metals. Compared with the alkali steels in team 1 and the alkaline planet metals in team 2, the shift metals space much less reactive. They don’t react conveniently withwateror oxygen, which describes why lock resistcorrosion.

Other nature of the change metals room unique. They space the only aspects that may useelectronsin the alongside highest—as well as the highest—energy levelas valence electrons. Valence electrons are the electrons that type bonds with other facets incompoundsand that normally determine the nature of elements. Shift metals are unusual in having very comparable properties also with various numbers of valence electrons. The change metals also include the only aspects that develop a magnetic field. Three of them have actually this property: stole (Fe), cobalt (Co), and also nickel (Ni).

Q:How is the variety of valenceelectronstypically concerned the nature of elements?

A:The number of valenceelectronsusually determines how reactive aspects are and the methods in i beg your pardon they react with other elements.

Those aspects Down Under

Transition metals include the facets that room most frequently placed listed below the routine table (the pink- and purple-shaded aspects in theFigureabove). Those the follow lanthanum (La) are dubbed lanthanides. They are all relatively reactive for shift metals. Those that follow actinium (Ac) are referred to as actinides. They are all radioactive. This means that they space unstable, for this reason they decay into different, an ext stable elements. Numerous of the actinides execute not take place in nature but are do inlaboratories.


· change metals are all the aspects in teams 3–12 that the periodic table. More than half of all elements are shift metals.

· change metals are typical metals, v properties such together a superior ability to conduct electrical energy andheat. They additionally have the metallic properties of luster, malleability, and also ductility. In addition, transition metals have highmeltingandboilingpoints and also high density.

· Thelanthanides and also actinidesare the change metals that space usually placed below the main part of the regular table. Lanthanides are relatively reactive for transition metals, and actinides are radioactive.

Explore More

At the following URL, click on any two of the transition metals and also read about their properties,atomic structure, discovery, and also uses. Then compose a paragraph comparing and also contrasting the 2 elements.



1. What are shift metals?

2. Define properties of transition metals.

3. Exactly how do shift metals different from metals in teams 1 and 2? exactly how are they different from all other elements?

4. Identify thelanthanides and actinides.

Groups v Metalloids

Characteristics of groups 13 - 16 the the periodic table.

· Identifyelementsin groups 13–16 the the routine table.

· list properties of a metalloid from every of this groups.


This photo represents a famous old Egyptian named Tutankhamen. Do you check out his heavy eyeliner? Most most likely the eyeliner was made of a mineral include antimony. This metalloid was generally used because that makeup through Egyptians between four and five thousand year ago. Now we understand that antimony is toxic, although Tutankhamen most likely didn’t recognize that. Antimony is found in team 15 the the routine table. Team 15 is one of four groups that the periodic table that containmetalloids.  

Groups 13–16

Groups 13–16 of the periodic table (orange in theFigurebelow) are the only teams that containelementsclassified asmetalloids. Unlike other teams of the periodic table, which contain facets in just one class, teams 13–16 contain elements in at the very least two various classes. In enhancement to metalloids, they also containmetals, nonmetals, or both. Teams 13–16 fall in between the shift metals (in groups 3–12) and the nonmetals calledhalogens(in group 17).


What AreMetalloids?

Metalloidsare the smallest course ofelements, containing simply six members: boron (B), silicon (Si), germanium (Ge), arsenic (As), antimony (Sb), and also tellurium (Te). Metalloids have some properties ofmetals(elements that have the right to conduct electricity) and also some properties of nonmetals (elements the cannot command electricity). Because that example, most metalloids can conduct electricity, however not and metals. Metalloids likewise tend to be shiny prefer metals, yet brittle favor nonmetals. Chemically, metalloids may behave like metals or nonmetals, relying on their variety of valenceelectrons. You have the right to learn more about specific metalloids by clicking on the facet symbols in the periodic table at this URL:http://www.chemicool.com/.

Q:Why go the chemical habits of an facet depend on its number of valenceelectrons?

A:Valenceelectronsare the electron in an atom’s outerenergy levelthat might be affiliated inchemical reactionswith otheratoms.

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Group 13: Boron Group

Group 13 of the periodic table is additionally called the boron group due to the fact that boron (B) is the first element at the height of the group (seeFigurebelow). Boron is also the just metalloid in this group. The various other four elements in the group—aluminum (Al), gallium (Ga), indium (In), and also thallium (Tl)—are allmetals. Team 13 facets have 3 valence electrons and are reasonably reactive. Every one of them aresolidsat roomtemperature.