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What causes the tungsten atoms to evaporate from filament of a bulb?
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Is electric bulb glowing a example of chemical or physical changes?
It is a physical change. When you supply electricity, the electrons jump to higher energy state. When they come back to their level, it emits energy which falls in the visible region of light. The atoms of the filament (Tungsten) are not going through any change, that changes their chemical properties. Tungsten, still remains tungsten!
How does heat affect atoms?
higher ambient (atmospheric) temperacha means dem atoms get more energy. this means they move about loads more blud. then then get hotter. if they are liquids, more of them than normal will have enough energy to evaporate blud. that's why when it is bare hot, puddles dry up quicker blud.
If the distance between W atoms in tungsten metal is 2.74 What is the atomic radius of a tungsten atom in this environment This radius is called the metallic radius?
r= d/2 r= 2.74/2 r= 1.37
Is tungsten v bromide covalent or metallic bond?
WBr5 is a molecular compound. Its molecular formula is W2Br10, and consists of 2 W atoms with 6 Br atoms arranged octahedrally which share an edge , a so-called bioctahedral structure. The bonding is covalent, with an electronegativivty difference of just 0.6
Why is titanium a poor conductor of thermal heat and electricity?
Actually tungsten is a great conductor of heat and electricity. Tungsten is used a light bulb filaments. If Tungsten was a poor conductor of heat and electricity the bulb in the circuit would not glow because there wouldn't be electricity passing through the circuit. Tungsten is also used as an electrode in gas tungsten arc welding. Electricity passes through the tungsten (negative) and moves to the workpiece (positive) for most applications.
Why do lightbulbs burn out?
They burn out from 1) the rapid heating and cooling of the Tungsten filament, and 2) from the tungsten atoms being released from the metal filament by way of the extremely high temperatures. Eventually the tungsten metal fails and the filament breaks.
How does the halogen par lamp?
A halogen lamp a uses a tungsten filament, but it is encased inside a much smaller quartz envelope. Because the envelope is so close to the filament, it would melt if it were maA halogen lamp also uses a tungsten filament, but it is encased inside a much smaller quartz envelope. Because the envelope is so close to the filament, it would melt if it were made from glass. The gas inside the envelope is also different -- it consists of a gas from the halogen group. These gases have a very interesting property: They combine with tungsten vapor. If the temperature is high enough, the halogen gas will combine with tungsten atoms as they evaporate and redeposit them on the filament. This recycling process lets the filament last a lot longer. In addition, it is now possible to run the filament hotter, meaning you get more light per unit of energy. You still get a lot of heat, though; and because the quartz envelope is so close to the filament, it is extremely hot compared to a normal light bulb. de from glass. The gas inside the envelope is also different -- it consists of a gas from the halogen group. These gases have a very interesting property: They combine with tungsten vapor. If the temperature is high enough, the halogen gas will combine with tungsten atoms as they evaporate and redeposit them on the filament. This recycling process lets the filament last a lot longer. In addition, it is now possible to run the filament hotter, meaning you get more light per unit of energy. You still get a lot of heat, though; and because the quartz envelope is so close to the filament, it is extremely hot compared to a normal light bulb.
What is the term for that bright light as a light bulb burns out?
I'm not sure there is an official name for it, I just always called it a flash. It happens because the tungsten filament is not pure tungsten, but an alloy to make the tungsten easier to draw into wire. Some of the alloying agents evaporate below the temperature of the operating filament. If enough evaporates in one spot, the resistance of that spot rises causing the spot to dissipate more power than the rest of the filament. When you turn the light off, the filament cools and its total resistance drops. When you turn the light on again, this low resistance causes a current surge. At the high resistance spot this current surge causes unusually high heating, vaporizing the tungsten at that point in a bright flash of light and burning out the bulb. Halogen bulbs delay this by running the filament very hot in a low pressure halogen gas enclosed in a quartz bulb to tolerate the high temperature. The halogen gas scavenges evaporated metal atoms, then migrates toward the filament. When the halogenated metal contacts the hot filament it dissociates, depositing the metal atom on the filament and the halogen goes back out to scavenge more evaporated metal. The dissociation process happens faster where the filament is hotter, which happens to be the spots that have evaporated the most so they tend to get filled in.
Where does a flashlight release its light?
There is a filament in the lightbulb usually and the batteries provide the energy to heat up the filament (in a lightbulb the little filament in TUNGSTEN). Once the filament heats (the filament is made of a metal), the atoms of the filament have a smaller electron circulating around them and the electrons get excited and jump from different orbits around atom and in so doing, produce wavelengths of light... and this is the light you see.
Does a flashlight release it's lights?
There is a filament in the lightbulb usually and the batteries provide the energy to heat up the filament (in a lightbulb the little filament in TUNGSTEN). Once the filament heats (the filament is made of a metal), the atoms of the filament have a smaller electron circulating around them and the electrons get excited and jump from different orbits around atom and in so doing, produce wavelengths of light... and this is the light you see.
How many moles of tungsten atoms are in 4.81023 atoms of tungsten?
Not many! ( how do you people keep coming up with fractional atoms? ) 4.8 atoms tungsten (1 mole tungsten atoms/6.022 X 10^23) = 8.0 X 10^-24 moles tungsten atoms
In an light bulb what energy produces thermal energy which then produces radiant energy?
When the lightbulb is placed in a bulb holder, a voltage is applied across the metallic filament. As a result, a current of electrons now flows from through the filament. As the electrons flow through the metallic filament, they collide with the atoms in the filament, causing the atoms to vibrate. This vibration is what causes the temperature of the filament to rise. When the temperature of an object increases, it will always radiate thermal energy via black body radiation. A more intuitive explanation, is that the atoms in the object vibrate faster and faster as a function of temperature. As a result, the charges around the atoms will vibrate. When charges accelerate and decelerate, they induce an electromagnetic wave, or what is commonly known as light, which radiates away from the atoms. The wavelength of the light that is emitted from the atoms depends on the vibration of the atoms, or equivalently the temperature of the material. So the faster the vibrations, the higher the frequencies and amplitudes (intensity) of the light. The question is misleading in that it implies that light and thermal energy are two different forms of energy. In fact, light and thermal energy are the exact same thing, but just at different wavelengths. The light that we see in our eyes corresponds to wavelengths in the visible spectrum (450nm - 650nm), whereas thermal radiated energy is at longer wavelengths (infrared). Therefore, when the filament is heated up, the atoms vibrate, which causes light to be emitted over a large spectrum of wavelengths, some of that is visible light and some of that is infrared light (heat). This is how a lightbulb can generate both "light" and "thermal energy."
Is electric bulb glowing a example of chemical or physical changes?
It is a physical change. When you supply electricity, the electrons jump to higher energy state. When they come back to their level, it emits energy which falls in the visible region of light. The atoms of the filament (Tungsten) are not going through any change, that changes their chemical properties. Tungsten, still remains tungsten!
How many moles are equal to 5.82 x 1023 atoms of tungsten?
5,82 x 1023 atoms of tungsten equal 0,966 moles.
How many atoms are present in 0.0845 moles of tungsten?
0.0845 moles of tungsten is equal to 0,50887.10e23.
What is the filament inside the bulb made up of?
Incandescent light bulbs have filaments which are made mainly from the element tungsten and/or alloys which include tungsten.Tungsten is the metal element used for the filaments in incandescent light bulbs.Experiments were made with different materials to use as the filament, including natural fibres, pure metals and alloys of different metals, to find the material which had the longest life whilst glowing brightly enough to give out visible light. The metal Tungsten was found to be the best, because of its high melting point (almost 3700 K) and good resistance to electrical current.For more information see the answer to the Related Question shown below.Carbonized cotton was originally tried, and had moderate success. However, the material that finally worked the best was a filament made of tungsten, which shone brighter and lasted much longer.It is made up of Tungsten which have an melting point of 3380 degree Celsius.
How many atoms are present in 104 mol of tungsten?
no
