Families of Elements. By: Scarlett Stein College Chemistry Period: 6

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1 Families of Elements By: Scarlett Stein College Chemistry Period: 6

2 Group 1- Alkali Metals Alkali Metals only one valence electron. These elements form a +1 cation. This group is rarely found in nature as pure elements, because these metals are so reactive. More commonly found combined with other elements to form compounds.

3 Element: Rubidium (Rb) Rubidium is an Alkali Metal because it behaves violently in water and is soft. Atomic Number- 37 Rubidium came from the Latin word rubidus, and means deepest red. This element can be used to give fireworks a red/violet color. It is the 23rd most abundant element in Earth s crust. Rubidium was discovered in 1861 by Robert Bunsen and Gustav Kirchhoff, using a spectroscope.

4 Group 2- Alkaline Earth Metals Alkaline Earth Metals have two valence electrons. They react to form a +2 cation. Each individual element burns a different color. These metals react with halogens to form compounds called halides.

5 Element: Beryllium (Be) This element is placed in Group 2 because their outer electron structure are all similar. All elements are also shiny, fairly soft, and harder than Alkali Metals. Atomic Number- 4 When burned, white flames are given off. Beryllium forms covalent bonds, where the rest of the metals in group 2 form ionic bonds. It is the 5th most abundant element in Earth s crust. Beryllium is considered a carcinogen, which means it can cause cancer to humans. It is very poisonous to humans.

6 Groups Transition Metals Transition Metals do not follow the traditional valence electron rule. But, they lose electrons to form positive ions. These elements are less reactive than Groups 1 and 2.

7 Element: Cobalt (Co) Cobalt is located under transition metals because of the odd valence electron rule it follows, and because it is one of only three that have a magnetic force. Atomic Number- 27 Cobalt came from the German word for goblin, or evil spirit, kobald. Also from the Greek word for mine, cobalos. Radioactive 60Cobalt is used in the treatment of cancer. Cobalt was founded in 1735 by a Swedish chemist named George Brandt. This element is widely used in batteries.

8 Group 13- Boron Family The Boron Family has three valence electrons. They react to form a +3 cations. They begin the start of the semi-metal staircase. These elements do not occur free in nature.

9 Element: Boron (B) This element is in group 13 because it is a metalloid and because it has three valence electrons in its outer-most layer. Atomic Number- 5 Boron is the only non metal in this family, the rest of the elements are just metals. Boron is used in detergents, and also as semiconductors in electrical devices. This element is an essential nutrient for all green plants. Boron in its crystalline form is very unreactive, but during its amorphous form it is very reactive.

10 Group 14- Carbon Family The Carbon Family has four valence electrons. They form covalent bonds, and do not like to share. The elements in this group are classified as metals (2), nonmetals (1), and metalloids (2). These elements are also solid at room temperature.

11 ELement: Carbon (C) Carbon is located under Group 14 because since Carbon is a nonmetal, it has to form covalent bonds, meaning they must share. All elements in this group can form four bonds. This is the most out of all the families. Atomic Number-6 Carbon is the key ingredient for most life on Earth. Carbon occurs naturally as Carbon-12, which makes up 99% of the Carbon in the universe. To this day, it is unknown who discovered Carbon. This element got its name from the Latin word carbo, meaning coal.

12 Group 15- Nitrogen Family The Nitrogen Family has five valence electrons. They react to form a -3 anion. The elements in this group are classified as metals (1), nonmetals (2), and metalloids (2). Except for Nitrogen, which is a gas, the rest of the elements are solid at room temperature.

13 Element: Nitrogen (N) Nitrogen is in Group 15 because it has five valence electrons, along with the rest of the elements to be found in this group. Atomic Number- 7 Nitrogen is a colorless, odorless, and tasteless gas in normal conditions. This element makes up about 78% of the air we breathe. Nitrogen Acid is a strong acid used in fertilizers. Over 98% of Saturn s largest moon named Titan is made up of an atmosphere of Nitrogen.

14 Group 16- Oxygen Family The Oxygen Family has six valence electrons. They react to form -2 anions. Can be found both free and in combined states in nature. Oxygen is a gas, where the rest of the elements are solids.

15 Element: Sulfur (S) Sulfur belongs to Group 16 because it has six valence electrons, along with each other element in this group. Atomic Number- 16 Sulfur is a yellow, tasteless, and odorless element. It is the 16th most abundant element in Earth s crust. Sulfur is often found near the edges of volcanoes and hot springs. This element has been used since ancient times and is even mentioned in the Bible.

16 Group 17- Halogens Halogens have seven valence electrons. They react to form a -1 anion. Astatine is extremely rare and is highly radioactive, where the rest of the elements are widely used. These elements all share the ability to form salts.

17 Element: Chlorine (Cl) This element is classified under Halogens because it is a poor conductor and forms salts, just like the other halogens. Atomic Number-17 Chlorine was used back in 1785 as a bleaching agent, and is still in effect today. The word Chlorine comes from the Greek word khloros, meaning greenishyellow. This element is used to disinfect water. Chlorine was also used during World War I, beginning in 1915.

18 Group 18- Noble Gases Noble Gases have eight valence electrons. Because of their full outer shells, these elements are very inert and stable. All of the Noble Gases except for Radon has stable isotopes. These elements were used to create a safe atmosphere, because of their stable nature.

19 Element: Helium (He) This element is considered a Noble Gas because the outer shell is full with eight valence electrons, meaning its happy, or content. It does not tend to lose or gain electrons, which means it doesn t react. Helium only has two electrons, and it follows the duet rule. Atomic Number-2 Helium has the lowest melting and boiling points of any substance. Because Helium is non flammable, this is why it is safely used in balloons. Helium is the second most abundant element, following behind hydrogen. Helium was discovered in the Sun s atmosphere before it was found on Earth.

20 Lanthanide-(Atomic # s 57-71) The elements under this group can have either one or two valence electrons, just depending on which element is being observed. All types of ions can be formed when looking under Lanthanides. n It all matters on which element is picked. For example, some can forma +2, or +4, where others form ionic compounds. These elements are known as Rare Earth Elements. Fourteen out of the fifteenth elements in Lanthanides are located in the f-block. The other straggler can be found in the d-block.

21 Element: Ytterbium (Yb) Ytterbium is known as a Lanthanide because it is difficult to separate, which is why it is also known as a Rare Earth Element. Atomic Number-70 This element got its name from the Swedish village of Ytterby. This element is fairly stable in air, but is dissolved slowly when placed in water. Ytterbium was the first Rare Earth Element to be discovered and is also the most common as well. Ytterbium metal costs about $360 per kilogram.

22 Actinide- (Atomic # s ) The elements follow very similarly to Lanthanides, and also follow the Aufbau rule when it comes to valence electrons. Each element under this category forms positive ions (cations), but the exact amount varies by the certain element being studied. These elements are all considered to be radioactive. Actinides are sometimes known as Inner Transition Metals because their atomic numbers fall between the 1st and 2nd elements in the last two rows of Transition Metals.

23 Element- Uranium (U) Uranium is listed as a Actinide because it is radioactive, tarnishes in the air, and combine directly with most nonmetals. Atomic Number-92 Uranium is named after the planet Uranus. This element was discovered by Martin Klaproth in Uranium has been dated back to be used in Ancient Rome for coloring glass. The first atomic bomb to be dropped on Japan during World War II contained an uranium core.

24 Hydrogen- (H) Hydrogen is a nonmetal, and is shown isolated by itself because it only has one electron in its outer layer. Atomic Number-1 Hydrogen is the lightest, simplest, and most commonly found element in the Universe. This element got its name from the Greek word hydro, meaning water, and genes, meaning creator. It is colorless, odorless, and tasteless. Hydrogen plays a major role in powering stars through fusion reactions.