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Alkaline Earth Metals video

Added Feb 20, 2018 •

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the alkaline earth metals are generally softer than most other metals and their react readily with water particularly when heated each has two valence electrons in its outermost John shell they are powerful reducing agents that readily give up electrons to other substances the element beryllium can absorb large amounts of heat which makes it useful for spacecraft and aircraft Construction magnesium is a light metal it is combined with other metals to make racing bicycles airplanes missiles and other products that need to be lightweight and strong calcium is an essential element for countless living organisms it forms the foundation for everything from shells to teeth and bones strontium goes into colorful flares and fireworks phosphorescent paints a radioactive version of this element is one of the most deadly byproducts of nuclear fallout barium is a heavy silver metal that is used in spark plugs vacuum to and fluorescent lamps and radium is an intensely radioactive element that doctors once often you to destroy cancer cells in their pure forms the elk first metals are shiny silvery gray Meadows they have relatively high melting and boiling points and they are good conductors of heat and electricity these metals have a gray white luster when they are freshly cut but they tarnish quickly when exposed to air the heavier members of the group tarnish especially quickly beryllium the lightest of the alkaline earth metals is hard enough to scratch glass but barium the heaviest is only slightly harder than lead the alkaline earth metals react readily with water especially when they are heated the combine easily with other elements and as a are never found in their pure uncombined forms in nature although they are harder stronger and denser than the alkali metals beer nearly as chemically reactive the alkaline earth are so reactive because they are very electropositive this means that like the alkali metals they easily lose electrons to other elements let's take a closer look at the periodic table on the periodic table the elements are listed in order of their atomic number the atomic number represents the number of protons in an element nucleus and its normal or ground state this nucleus is surrounded find equal number of electrons and as the atomic number increases generally so does the size and mass of the atoms as you read the periodic table from top to bottom each horizontal line call the. Each. Represents the number of electron shells the elements atoms normally have for example there are four electron shells in an atom of calcium so what lies in period 4 meanwhile an atom of barium in. 6 has 6 electron shells as you read across the table from left to right the vertical lines of elements are called groups elements in a group have the same number of electrons in their outermost electron shells these outermost electrons are called valence electrons and they dictate how elements interact elements in the same group generally interact with other elements in similar ways none of the elements greater than atomic number 83 are completely stable all of these elements including radium are radioactive all alkaline earth residing group two because they each have two electrons in their outermost electron shell because atoms need eight electrons in their valence shell to be stable the two valence electrons in the alkaline earth metals makes them stable nearly as unstable as the alkali metals which only have one valence electron as a result of the alkaline earth metals easily lose their two electrons during chemical reactions and as you move from beryllium to radium the atoms hold on their valence electron becomes weaker making each alkaline earth metal more reactive than the one before it element number for on the periodic table is beryllium the atomic symbol for beryllium is b e beryllium is a hard strong gray metal that can be polished to a high Sheen Trillium gets its name from Beaver last the Greek word for the mineral Beryl the really am is classified as an alkaline earth metal he flies on the periodic table second Row. 2 each atom of beryllium consists of a cloud of electrons surrounding a compact nucleus that contains almost all the atom's mass in the most common form of beryllium its nucleus has four if we charge protons plus 5 on charge neutrons William has for negatively charged electrons to balance its 4 protons these electrons are found in two orbital shell surrounding the which can be visualized as being built up from the nearest preceding noble gas helium helium has two electrons distributed in a single orbital shell the two additional electrons beryllium are found in the spherical 2's orbital shell really react easily and will typically lose these two valence electrons when combining with other elements beryllium is a Sibley light metal with a density of 1.8 grams per cubic centimeter in this experiment beryllium is placed on a scale with a smaller piece of tungsten place on the left hand side tungsten is one of heaviest of All Metals with a density of 19.3 grams per cubic centimeter as a result of a much larger amount of beryllium is needed to balance the smaller amount of tungsten because beryllium can absorb large amounts of heat is useful for making spacecraft missiles and other aircraft it is also used in lightweight metal alloys and x-ray tube windows element number 12 on the periodic table is magnesium the atomic symbol for magnesium is mg magnesium is a white grayish white metal with a low density magnesium gets its name from the ancient Greek region known as magnesia where magnesium ores were commonly found magnesium is classified as an alkaline metal in the periodic tables third row. The rig each atom of magnesium consists of a cloud of electrons surrounding a compact nucleus that contains almost all the atom's mass in the most common form of magnesium its nucleus has 12 positively charged protons plus 12 uncharged neutrons magnesium has 12 negatively charged electrons to balance it protons these electrons are found in three orbital shell surrounding the nucleus which can be visualized as being built up from the nearest preceding noble gas Nyan Nyan 10 electrons distributed within 2 orbital shells the two additional electrons in magnesium are found in the spherical 3s orbital shell magnesium reacts easily and will tip it lose its two valence electrons when interacting with other elements in this experiment a piece of coiled magnesium ribbon is ignited in a propane Flame reacting with the oxygen in the air it blows and gives off a lot of heat it is important during this experiment that the experimenter do not look directly at the bright light for too long as it is bright enough to burn the retina in the eye the white residue that remains on the couch after the flame is removed is magnesium oxide due to the bright white light it produces when it is burned magnesium is often used in pyrotechnics photographic bulbs and flares magnesium metal alloys are used to make airplanes Rockets cameras and horseshoes element number 20 on the periodic table is calcium calcium is a silvery white metal that tarnishes quickly when exposed to air calcium never occurs freely in nature because it is highly reactive and easily forms compounds with oxygen in water calcium gets its name from the Latin word cows which means line because limestone is one of the sources of the element calcium is class why does an alkaline earth metal and lies in the periodic tables for throw. For each atom of calcium consists of a cloud of electrons surrounding a compact nucleus that contains almost all of the at Mass in the most common form of calcium its nucleus has 20 positively charged protons plus 20 uncharged neutrons calcium has 20 negatively charged electrons to balance its 20 protons these electrons are found in for orbital shells surrounding the nucleus which can be visualized as being built up from the nearest preceding noble gas Argon Oregon has 18 electrons distributed among three orbital shells calcium has two more electrons than Argon the two electrons are found in the sphere shaped 4S orbital shell these two valence electrons calcium very chemically active and many other elements calcium is a silvery white hard metal which is difficult to cut when exposed to air it forms a thin white fear of oxide called mine so the metal remain silvery for only a few minutes once several pieces have been cut they are dropped into a bowl of water the calcium metal reacts slowly with the water milky white calcium hydroxide and Bubbles of hydrogen gas after 10 minutes the water in the bowl becomes cloudy and highly alkaline with dissolve lime did you do it reactivity metallic calcium has very few uses its compounds on the other hand have many uses calcium carbonate is used to make white paint cleansing powder toothpaste and stomach antacids compounds are used to make drywall plaster and natural fertilizers the human skeleton is incredibly strong yet remarkably light the 206 make up our skeleton support our bodies allow us to move around the world and protect the vital organs inside us and every one of our bones depends on the element calcium we use calcium to help regular heartbeat and blood but 90% of the calcium in our bodies is in our bones our bodies use calcium mostly in the form of phosphate and carbonate salt to form and maintain our bones and teeth calcium is especially important when you were young because it helps bones grow stronger bigger and healthier bones make up only 18% of our total body weight but they have to deal with all the impacts and stresses we put our bodies through everyday Zara hard mix of calcium and other minerals on the outside but they are spongy on the inside and the end of our bones have a honeycomb structure of arches struts these formations direct the force of impact into the strong middle section of the bone being shaken hard in some places and spongy and Hollow and others helps make our bones very strong but still light bones are living things they are made up of living cells embedded in the calcium carbonate Matrix that makes up the hard part of our bones B cells are constantly repairing and replacing the calcium and other minerals in bone this becomes especially important after an injury when a bone breaks the body and mediately sends in the repair team cells called osteoblasts begin the repair work by creating a layer of liquid calcium another minerals are drawn to the damaged area strengthening and eventually forming a new bone the cells are constantly on the lookout for bones that have weakened from daily activity cheer destroying cells called osteoclast break down we can bone so they can be built up again within 10 years these cells break down and replace every bone in your body which is a very especially for people who enjoy it active lifestyle send an ox that come with it element number 38 on the periodic table is strontium the atomic symbol for strontium is Sr strontium is a soft silver yellow metal that can be found in three different crystalline forms strontium is name for strontium Scotland tell me the mines were the first strontium bearing minerals were found strontium is an alkaline earth metal and lies in the periodic tables 5th Row. 5 each atom of strontium consists of a cloud of electrons rounding a compact nucleus that contains almost all of the atom's mass in the most common form of strontium its nucleus has 38 positively charged protons plus 50 uncharged neutrons in strontium has 30 negatively charged electrons to balance its 38 protons these electrons are found in 5 orbital shell surrounding the nucleus which can be visualized as being built up from the nearest preceding noble gas Krypton Krypton has 36 electrons distributed among for orbital shells the two additional electrons in strontium are found in the spear shaped 5S orbital shell these to outermost valence electrons man has strontium reacts with other elements the silvery white metal strontium reacts easily with air so this sample is protected by a thin layer of paraffin wax and kerosene when the protective layer is burned off the floor big nights the metal which burns in air with an intense Crimson light when the metal burns it produces a mixture of white strontium oxide and strontium nitride volatile strontium salt such as these are often used in fire and Signal flares because they produce a brilliant crimson color most strontium is used to produce glass for television picture tubes the element is sometimes combined with iron to make magnets and is also used in making pirotecnia and phosphorus and pants in the spring of 1986 the worst nuclear reactor disaster in history occurred at the Chernobyl nuclear power station in Northern Ukraine to run a test Engineers had deliberately disabled the emergency backup systems in one of the reactors but instead of Simply testing the reactor they accidentally started an Unstoppable nuclear chain reaction in the core reactor number 4 on April 26th the reactor exploded ripping the top of the reactor containment building and blowing radioactive material High into the atmosphere as the reactor core fire spread to the nearby buildings and as they burn the core released more and more radioactive materials but as the danger of the explosion became more apparent they called for the evacuation of Chernobyl pripyat and other buy towns the fires of the Chernobyl plant range for more than a week and the burning nuclear core was brought under control only after a cement mixture was dropped onto it from the air the explosion and the fires were 8 tons of nuclear fallout into the atmosphere nuclear fallout is made of radioactive particles that are scattered through the Earth's atmosphere by winds and air currents the Chernobyl release created a huge cloud of Fallout they caused extensive harm across Eastern and Northern Europe this serious danger of nuclear fallout is that it contains radioactive isotopes of the element strontium cesium carbon and iodine in high doses these Isotopes can cause severe health problems or even death one of these Isotopes strontium-90 remains radioactive for decades and since strontium and calcium are both chemically similar earth metals the tissues of animals and plants absorb strontium as if it were calcium when humans consume contaminated foods and liquids the strontium-90 accumulates in their systems and can cause genetic damage or lie to leukemia bone cancer and other diseases strontium is particularly dangerous for children because it is easily deposited in there growing bones Ukrainian officials estimated that at least 8,000 people died as a result of the Chernobyl accident and the cleanup of the radioactive materials it released millions of Europeans live on radiation-contaminated land and countless more will likely suffer harmful long-term effects when the Chernobyl release of strontium and other radioactive elements element number 56 on the periodic table is barium the atomic symbol for barium is ba a soft heavy silvery gray metal barium oxidizes very rapidly barium derives its name from Ferris Greek for heavy classified as an alkaline earth metal barium lies in the periodic table 6th row. 6 each atom of barium consists of a cloud of electrons surrounding a car back nucleus that contains almost all the atom's mass in the most common form of barium its nucleus has 56 positively charged protons 82 on charged neutrons barium has 56 negatively charged electrons to balance it's 56 protons these electrons are found in six orbital shell surrounding the nucleus which can be visualized as being built up the nearest preceding noble gas Xenon Xenon has 54 electrons distributed among five orbital shells barium has two more electrons than Xenon Beach to Bay electrons are found in the spherical 6s orbital shell an influence how Burien interacts with other elements barium is a metallic element resembling calcium chemically here a piece of barium is placed in a very hot flame it burns with a very bright blue green flame and melts easily although Barrymore's are heavy metallic barium isn't that quite light with a density of proximately half that of iron barium nitrate burns with a bright green color and is used in fireworks and Signal flares barium is used in vacuum tubes as it get her a material that vines with and removes Trace gases barium sulfate is it good absorber of X-rays and when swallowed can be used to produce x-ray images of the intestinal tract barium peroxide forms hydrogen oxide when it is mixed with water and it is used as a bleaching agent that activates when wet number 88 on the periodic table is radium the atomic symbol for radium is RA seen here in the glowing dials of this watch face radium is a brilliant white metal that slackens when exposed radium glows in the dark and is extremely radioactive more than a million times more radioactive than uranium radium gets its name from the Latin word for Ray radius because of the Radioactive raise it a miss redeem is classified as an alkaline earth metal it lies in the periodic table 7th row. 7 each atom of radium assets of a cloud of electrons surrounding a compact nucleus that contains almost all of the atom's mass in the most common form of radium its nucleus has 88 positively charged protons plus 138 uncharged neutrons radium has 88 negatively charged electrons to balance its 88 protons these electrons are found in 7 orbital shell surrounding the nucleus which can be visualized as being built up nearest preceding noble gas radon radon has 86 electrons distributed among six orbital shells radium has two more electrons than radon both of these electrons found in a sphere shaped 7s orbital shell it is these two valence electrons that determine how radium reacts with other chemicals redeem is represented here by the display of nuclear fireworks inside a how old is Ben therascope a small piece of radium is sealed within the device and as the radian atoms undergo natural radioactive decay they release alpha particles these Alpha particles travel at over 20,000 miles per hour and when they strike of zinc sulfide screen inside the device photons of visible light are released in a process called ventilation this produces the thousands of tiny Flash greenish light that are visible through the devices magnifying lens each flash of light indicates a single atom of radium decaying radium is highly radioactive so it's used as Limited in the past small amounts of radium were used to make glow-in-the-dark paint for watches aircraft dials and other instrument displays but less dangerous alternates have largely replaced those early uses today the 8th it is primarily used in the treatment of cancer the gamma rays it produces kill cancer cells and radium is used to produce radon gas that is also used to combat some cancers one of the most significant medical advancements of the 20th century was the invention of nuclear medicine nuclear medicine allows doctors to use small amounts of radioactive elements to get in inside you with a patient's body without surgery when doctors find tumors radioactive materials may also be placed directly into a patient's body where the radioactivity helps fight the growth of cancer cells the roots of nuclear medicine began in France in 1896 when Professor on Reba Krall discovered that uranium was Radioactive background Discovery radiation soon taunted other scientists search for radioactive elements two scientists the polish-born Marie and Pierre Curie made discoveries that would change the face of Medicine using equipment design by Pierre Siri measured and analyzed thousands of mineral samples in early 1898 she discovered a second radioactive element thorium by the end of that year the curies had discovered two more Radioactive polonium and radium thorium and uranium had about the same radioactive strength but polonium was 10000 times greater and radium strength was more than a me times that of uranium the discovery of such a highly radioactive element Rock the scientific World they work was extremely important the discovery of opened up a whole new it's been described as the new age in physics doctors who discovered that exposure to strong radioactivity like that given off by radium could kill cancer cells an early medical technique involves inserting radium needles directly into tumors radiation treatments helps millions of cancer patients throughout the world battle their disease Zoe radium iodine and cesium have replaced radium in radiation treatment nuclear medicine remains an effective method for detecting and treating cancer creation terapias a localized treatment of cancer involve external beam radiation and insertion of radioactive materials into the too much radiation therapy was actually in use within a year of discovery of radiation since then I should become a highly sophisticated treatment of cancer of all cancers radiation is the second most used after surgery long exposure to radioactivity radioactive elements can kill cancer cells extended exposure to them can also cause cancer marie-therese work with radiant produced painful scars on her hands and worse her repeated contact with radioactive elements eventually brought her life to an end she died of leukemia before reaching the age of 70 but her pioneering work made her the first person to win laid the groundwork for countless medical advances and prolong the lives of millions of people

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