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Chap 12-2
The Periodic Table
Question | Answer |
---|---|
Why are the properties of the elements in a group are similar? | The atoms of the elements have the same number of electrons in their outer energy level |
In order to have a complete set of electrons in their outer energy level what will atoms often do? | Take, give, or share electrons with other atoms |
Elements whose atoms undergo such processes to have a complete set of electrons are called what? | Reactive |
Once elements whose atoms are reactive can combine to form what? | Compounds |
What is the name for elements in Group 1? | Alkali metals |
Does Group 1 contain metals, metalloids, or nonmetals? | Metals |
How many electrons are in the outer level of alkali metals? | 1 |
What is the reactivity of alkali metals? | Very Reactive |
What are other properties of alkali metals? | Softness, color of silver, shininess, low density |
Do alkali metals share chemical and physical properties? | Yes |
Why are alkali metals are the most reactive metals? | Their atoms can easily give away the one outer-level electron |
Why are pure alkali metals are often stored in oil? | The oil keeps them from reacting with water and oxygen in the air |
Alkali metals are so reactive that in nature they are found with what? | Combined with other elements |
Do compounds formed from alkali metals have many uses? | Yes |
What are some example of combined alkali metals? | Sodium chloride (table salt) is used to flavor your food and potassium bromide is used in photography. |
How many elements are alkali metals? | 6 |
What are some physical and chemical properties examples of alkali metals? | They are soft enough to cut with a knife and they react with water to form hydrogen gas |
What is the name for elements in Group 2? | Alkaline-earth metals |
Does Group 2 contain metals, metalloids, or nonmetals? | Metals |
How many electrons are in the outer level of alkali-earth metals? | 2 |
What is the reactivity of alkali-earth metals? | Very reactive but less reactive than alkali metals |
What are other properties of alkali-earth metals? | The color of silver and higher densities than alkali metals |
Is it more difficult for atoms to give two electrons than to give one when joining with other atoms in Group 2? | Yes |
Does Group 2 elements and their compounds have many uses? | Yes |
What are some examples of Group 2 elements and their compounds ? | Magnesium can be mixed with other metals to make low-density materials used in airplanes, and compounds of calcium are found in cement, chalk, and even you |
How many elements are alkali metals? | 6 |
Is calcium, an alkaline-earth metal, is an important part of a compound that keeps your bones and teeth healthy? | Yes |
What is the name for elements in Group 3-12? | Transition Metals |
Does Group 3-12 contain metals, metalloids, or nonmetals? | Metals |
How many electrons are in the outer level of transition metals? | 1 or 2 |
What is the reactivity of transition metals? | Less reactive than alkaline-earth metals |
What are other properties of transition metals? | Shininess, good conductors of thermal energy and electric current, higher densities and melting points than elements in Groups 1 and 2 (except for mercury) |
How many elements are transition metals? | 38 |
What are some example of transition metals? | Mercury used in thermometers, gold made into a ring, iron used to make a shovel |
Are all transition metal silver colored? | No, because gold, a transition metal, proves it |
What are some properties and an example of lanthanides? | The lanthanides are shiny, reactive metals; Some of these elements are used to make steel and color red appears on a computer monitor because of a compound formed from europium that coats the back of the screen |
What are all atoms of actinides? What can the atoms do? | All atoms of actinides are radioactive, or unstable; the atoms of a radioactive element can change into atoms of another element |
Which elemnts listed after a specific element don't occur in nature? Where are they made? | Elements listed after plutonium, element 94, do not occur in nature; They are made in laboratories. |
What is an example of an actinide? | Very small amounts of americium, element 95, are used in some smoke detectors |
How many Lanthanides and Actinides, or rare earth elements are found? | 30 |
What is the name for elements in Group 13? | Boron Group |
Does Group 13 contain metals, metalloids, or nonmetals? | One metalloid and five metals |
How many electrons are in the outer level of the boron group? | 3 |
What is the reactivity of the boron group? | Reactive |
What are other properties of the boron group? | Solids at room temperature |
What is the most common element from Group 13? | Aluminum, it is even the most abundant metal in Earth’s crust |
Until what time was aluminum was considered a precious metal and why? | Until the 1880s, because the process used to make pure aluminum was very expensive |
During what years did Emperor Napoleon III of France used aluminum dinnerware and why? | During the 1850s and 1860s, because aluminum was more valuable than gold |
Today, is the process of making pure aluminum is easier and less expensive than it was in the 1800s? | Yes |
Why is aluminum important now? | It is used in making aircraft parts and also used to make lightweight automobile parts, foil, cans, and siding |
Why can aluminum be used in so many things? | A thin layer of aluminum oxide quickly forms on aluminum’s surface when aluminum reacts with oxygen in the air; this layer prevents further reaction of the aluminum. |
What is the name for elements in Group 14? | Carbon Group |
Does Group 14 contain metals, metalloids, or nonmetals? | One nonmetal, two metalloids, and three metals |
How many electrons are in the outer level of the carbon group? | 4 |
What is the reactivity of the carbon group? | Varies among the elements |
What are other properties of the carbon group? | Solids at room temperature |
Can the nonmetal carbon can be found uncombined in nature? | Yes |
Can carbon form a wide variety of compounds? | Yes |
What are some example of these compounds found in the carbon group? | Proteins, fats, and carbohydrates, are necessary for living things on Earth. |
What two types of material that have very different properties, yet both are natural forms of carbon? | Diamond and Soot |
The metalloids silicon and germanium, also in Group 14, are used to make what? | Computer chips |
How is the metal tin useful since it is not very reactive? | The tin is less reactive than the steel is, the tin keeps the iron in the steel from rusting; so a tin can is really made of steel coated with tin |
What is the name for elements in Group 15? | Nitrogen Group |
Does Group 15 contain metals, metalloids, or nonmetals? | Two nonmetals, two metalloids, and two metals |
How many electrons are in the outer level of the nitrogen group? | 5 |
What is the reactivity of the nitrogen group? | Varies among the elements |
What are other properties of the nitrogen group? | Solids at room temperature (except for nitrogen) |
What is nitrogen at room temperature, and how much does it make up of the air you breathe? | It is a gas at room temperature and makes up about 80% of the air you breathe |
What is another use for nitrogen other than air? | Nitrogen removed from air can be reacted with hydrogen to make ammonia for fertilizers |
What's the difference between nitrogen and phosphorous? | Nitrogen is not very reactive and phosphorus is extremely reactive; in fact, in nature phosphorus is only found combined with other elements |
What is an example of phosphorous in use? | Simply striking a match on the side of this box causes chemicals on the match to react with phosphorus on the box and begin to burn |
What is the name for elements in Group 16? | Oxygen Group |
Does Group 16 contain metals, metalloids, or nonmetals? | Three nonmetals, one metalloid, and one metal |
How many electrons are in the outer level of the oxygen group? | 6 |
What is the reactivity of the oxygen group? | Reactive |
What are other properties of the oxygen group? | All but oxygen are solid at room temperature |
How much of oxygen makes up what we breathe? | 20% |
What is oxygen necessary for? | For substances to burn and oxygen is also important to most living things |
Other than oxygen, what is a commonly found member of Group 16? How is it found in nature? | Sulfur, it can be found as a yellow solid in nature |
Sulfuric acid is used in what? What is it make from? | The most widely used compound in the chemical industry, and is used from sulfur |
What is the name for elements in Group 17? | Halogens |
Does Group 17 contain metals, metalloids, or nonmetals? | Nonmetals |
How many electrons are in the outer level of halogens? | 7 |
What is the reactivity of halogens? | Very reactive |
What are other properties of halogens? | Poor conductors of electric current, violent reactions with alkali metals to form salts, never in uncombined form in nature |
What do the atoms of halogens do? | Combine readily with other atoms, especially metals, to gain that missing electron |
The reaction of a halogen with a metal makes what? | A salt, such as sodium chloride |
What are chlorine and iodine used as? How? | They are used as disinfectants; chlorine is used to treat water and iodine mixed with alcohol is used in hospitals |
What is similar and different about halogens? | The chemical properties of the halogens are similar and the physical properties are quite different |
What are example of halogens physical properties? | Chlorine is a yellowish green gas, bromine is a dark red liquid, and iodine is a dark gray solid |
What is the name for elements in Group 18? | Noble Gases |
Does Group 18 contain metals, metalloids, or nonmetals? | Nonmetals |
How many electrons are in the outer level of noble gases? | 8 (except helium, which has 2) |
What is the reactivity of noble gases? | Unreactive |
What are other properties of noble gases? | Colorless, odorless gases at room temperature |
Why do noble gases not need to lose or gain any electrons? | The atoms of these elements have a full set of electrons in their outer level |
Do noble gases react with other elements? | Under normal conditions, they do not react with other elements |
How much argon is in the atmosphere? What about the other noble gases? | Earth’s atmosphere is almost 1% argon, but all the noble gases are found in small amounts |
How is the unreactivity of the noble gases useful with lightbulbs? | Ordinary light bulbs last longer when they are filled with argon because argon is unreactive, it does not react with the metal filament in the light bulb even when the filament gets hot |
What happens with a more reactive gas in a lightbulb? | Might react with the filament, causing the light to burn out |
What is an examples of a noble gas? | The low density of helium makes blimps and weather balloons float and neon can be used to make “neon” lights |
How many electrons are in the outer level of hydrogen? | 1 |
What are other properties of hydrogen? | Colorless, odorless gas at room temperature, low density, explosive reactions with oxygen |
Why is hydrogen alone? | The properties of hydrogen do not match the properties of any single group, so hydrogen is set apart from the other elements in the table |
Where is hydrogen located? Why? | Hydrogen is above Group 1 because atoms of the alkali metals also have only one electron in their outer level |
What can hydrogen atoms do when joined with other atoms? | Atoms of hydrogen can give away one electron when they join with other atoms |
What are the physical properties of hydrogen like? | Those of nonmetals than those of metals |
Where is hydrogen found? | In stars |
What is the most abundant element in the universe? | Hydrogen |
What is hydrogen useful for? | Its reactive nature makes it useful as a fuel in rockets |
What forms from the result from hydrogen and oxygen? How does it help space shuttles? | Hot water vapor, helps guide the space shuttle into orbit |
Hydrogen reacts _________ with oxygen | Violently |