Name: hydrogen emission lines
Uploaded: 2020-03-26T07:22:25.000Z
Duration: 3 min 53 s
Channel: JoVE

K12 Standards

Texas Essential Knowledge and Skills

High School

Chemistry and Physics

IPC.7

IPC.7.E

Balmer Series

Atomlar ve moleküller, enerjiyi emdiklerinde ve serbest bıraktıklarında çok ilginç davranışlar sergilerler. Bir atomdaki elektronlar geleneksel olarak, temel durum olarak adlandırılan ve bire eşit n olarak etiketlenen en düşük enerji durumunda bulunurlar. Bununla birlikte, bir atom enerjiyi emdiğinde, elektronlar uyarılır ve daha yüksek bir enerji seviyesine hareket eder. Elektronlar daha düşük bir enerji durumuna veya temel duruma düştüğünde, fazla enerji yayılan ışık olarak serbest bırakılır.
Bir atomu, kabuklarda veya orbitallerde yörüngede dönen elektronlara sahip bir çekirdek olarak tanımlayan Bohr Modelinde tasvir edildiği gibi, bu enerji durumlarına aşina olabilirsiniz. Bu kabuklar enerji seviyeleri ile aynıdır ve n ile etiketlenir. Yayılan ışığın dalga boyu, yüksek ve düşük enerji seviyeleri arasındaki farka bağlıdır. Yüksek enerjili yayılan ışık, elektronların daha yüksek bir enerji seviyesinden gevşemesinden kaynaklanır ve düşük enerjili yayılan ışık, elektronların daha düşük bir enerji seviyesinden gevşemesinden kaynaklanır.
Emisyon spektrumu, bir dizi dalga boyunda yayılan radyasyonun bir ölçüsüdür. Saf element türlerinde, emisyon davranışı geniş bir spektrumdan ziyade belirli dalga boylarının çizgileri olarak görünür. Farklı atomlar farklı enerji seviyelerine sahip olduğundan, bu spektral çizgiler elementten elemente değişir ve bu elektronların uyarıldığında enerji durumları arasında yaptıkları geçişlere bağlıdır. Örneğin, hidrojen için altı adlandırılmış spektral çizgi serisi vardır, bunlardan biri Balmer Serisidir.
Balmer Serisi spektral çizgiler, elektronlar n = 3'ten daha yüksek bir enerji seviyesinden n = 2'ye geri döndüğünde meydana gelir. Balmer Serisi için görünür ışık tayfı 410, 434, 486 ve 656 nm'de spektral çizgiler olarak görünür. H alfa çizgisi, 656 nm'deki kırmızı çizgidir ve n= 3'ten n = 2'ye geçiş nedeniyle oluşur. Camgöbeği, mavi ve mor çizgiler, sırasıyla n = 4, 5 ve 6'dan n = 2'ye geri dönen enerji seviyesi geçişlerine karşılık gelir. Ek spektral çizgiler görünür aralığın dışında ölçülebilir.
Johann Balmer, Balmer formülünü kullanarak görünür çizgileri ölçtü. Burada lambda gözlemlenen dalga boyudur, c bir sabittir, n ikinin daha düşük enerji seviyesidir ve m daha yüksek enerji seviyesidir. Balmer denklemi ve Bohr Modeli'nin kombinasyonu bize birçok farklı elementin spektral çizgilerini tanımlayan Rydberg denklemini verir. Bu denklemde, lambda kaydedilen dalga boyudurve RH, Rydberg sabitidir. n-başlangıç ile işaretlenen başlangıç seviyeleri, elektronların uyardığı daha yüksek enerji seviyesini temsil eder ve n, elektronların geri gevşediği daha düşük enerji seviyesidir. Balmer serisi için, nfinal = 2.
Bu laboratuvarda hidrojen, helyum ve neonun emisyon spektrumlarını ölçecek ve gözlemleyecek ve spektral çizgilerin konumunu belirlemek için Rydberg Denklemini kullanacaksınız.

balmer serisi

Bohr Modeli
Niels Bohr, 1913'te hidrojen atomu için ayrık enerji durumlarının çekirdeğin etrafındaki sabit bir elektron yörüngesi ile ilişkili olduğunu tanımlayan bir model önerdi. Daha da önemlisi, bir atom elektronları durağan durumdayken enerjiyi boşaltamaz. Bir elektron ancak enerji durumlarını değiştirerek enerji yayabilir. Enerji durumlarını değiştirmek için, bir elektronun enerjiyi emerek veya yayarak bir yörüngeden diğerine hareket etmesi gerekir. Bu değişiklik ancak emilen veya yayılan enerji iki durum arasındaki farka eşitse meydana gelebilir. Elektronlar yörüngeler arasında bulunamazlar.
Kuantum sayısı, n, farklı enerji durumlarını etiketlemek için kullanılır. En düşük enerji durumu, n'nin bire eşit olduğu temel durumdur. Uyarılmış durumlar 2, 3, 4 vb. ile eşit n olarak etiketlenir. Temel durumdaki bir elektron, enerjisi temel ve ikinci durum arasındaki farka eşit olan bir fotonu emdiğinde, elektron uyarılır ve temel durumdan n= 2 uyarılmış duruma geçer. Fotonun enerjisi yer ile üçüncü durum arasındaki farka eşitse, elektron n=3 durumuna geçer.
Bohr'un modeline göre,n'inci seviyedeki bir elektronun potansiyel enerjisi aşağıdaki denklem kullanılarak hesaplanabilir:
<img src="/CDNSource/lm/labs/54/54_Concepts_1.jpg" alt="Bohr modeli enerji seviyesi formülü, En=-Rhc/n², elektron geçişleri ile ilgili, denklem." data-altupdatedat="1754907201000">
burada En potansiyel enerji, R Rydberg sabiti (1.0974 × 107 m-1), h Planck sabiti (6.62607004 × 10-34 m2·kg/s) ve c ışık hızıdır (~ 3 × 108 m/s). Elektronlar ayrıca kendiliğinden temel duruma veya başka herhangi bir düşük uyarılmış duruma geri dönebilir. Bu olduğunda, fazla enerji yayılan bir foton şeklinde salınır. Fotonun enerjisi, daha yüksek ve daha düşük enerji durumları arasındaki enerji farkına eşittir. Bu enerji, ışığın dalga boylarına karşılık gelir. Her atom türü farklı enerji seviyelerine sahip olduğundan, her geçişten yayılan ışık her atom için farklılık gösterir. Karışık moleküllerden oluşan bir örnek için, yayılan ışık, sürekli spektrum adı verilen bir dizi dalga boyu içerir. Tek bir elementin atomlarını içeren bir örnek için, yayılan ışık yalnızca belirli dalga boylarını içerir ve bunlar bir kez bir prizma ile ayrıldıktan sonra ayrı çizgiler olarak görülebilir.
<h4>Hidrojen Atomu</h4>
Spesifik olarak hidrojen atomuna bakıldığında, elektronlarının uyarılması, iki atomlu molekülH2'deki bağı bölmek için yeterli enerjinin emilmesini gerektirir. Molekülü bölmek için gerekenden daha fazla enerji kullanıldığından, hidrojen atomundaki elektronlar fazla enerjiyi emer ve daha yüksek bir enerji seviyesine uyarılır. Elektronlar kendiliğinden daha düşük bir enerji seviyesine döndüğünde, uyarılmış seviye ile daha düşük seviye arasındaki enerji farkına karşılık gelen ışık yayılır.
Enerji emisyonunu tartışırken, daha yüksek enerji seviyesi başlangıç seviyesi veya ni olarak kabul edilirken, daha düşük seviye son seviye veya nf olarak kabul edilir. Yayılan ışığın dalga boyları nihayetinde iki seviye arasındaki enerji farkına bağlıdır.
Saf bir hidrojen gazı örneğinde, emisyon spektrumu, hidrojen elementine özgü ayrı dalga boylarının farklı çizgileri olarak görünür. Bu çizgilerin bazıları elektromanyetik spektrumun görünür aralığında, bazıları ise ultraviyole veya kızılötesi aralıktadır.
<h4>Balmer Serisi</h4>
Hidrojen atomu spektrumundaki görünür çizgiler dizisi Balmer serisi olarak adlandırılır. Bu spektral emisyon çizgileri serisi, elektron yüksek enerji seviyesinden n=2 olan düşük enerji seviyesine geçtiğinde meydana gelir. Johann Balmer, bu spektral çizgileri sırasıyla n=6, n=5, n=4 ve n=3 enerji seviyelerinden n=2 seviyesine geçişlere karşılık gelen 410.2 nm, 434.1 nm, 486.1 nm ve 656.3 nm'de gözlemledi.
Balmer, yayılan ışığın bu dalga boylarını Balmer formülünü kullanarak ilişkilendirebildi.
<img src="/CDNSource/lm/labs/54/54_Concepts_2.jpg" alt="Dalga boyu hesaplama formülü λ=C(m²/(m²-n²)), spektroskopi analizi denklemi." data-altupdatedat="1754907201000">
Burada, λ gözlemlenen dalga boyudur, C bir sabittir (364.50682 nm), n 2 değerine sahip düşük enerji seviyesidir ve m, 3'ten büyük bir değere sahip olan daha yüksek enerji seviyesidir. Bu gözlem daha sonra Johannes Rydberg tarafından rafine edildi, burada R, Rydberg sabitidir.
<img src="/CDNSource/lm/labs/54/54_Concepts_3.jpg" alt="Rydberg formül denklemi; Atomik spektroskopide spektral çizgileri hesaplar." data-altupdatedat="1754907201000">
Bu denklemin yayılan ışığı tanımladığını unutmayın, bu nedenle daha yüksek enerji seviyesi başlangıç seviyesi veya ni olarak kabul edilirken, daha düşük seviye son seviye veya nf olarak kabul edilir. Balmer serisi durumunda, nf 2'ye eşittir. Bu denklem, bir elektronu başlangıç ve son enerji seviyeleri (ΔE) arasında hareket ettirmek için gereken enerjiyi hesaplamak için Bohr modeli ile birleştirildi.
<img src="/CDNSource/lm/labs/54/54_Concepts_4.jpg" alt="Enerji seviyesi geçiş denklemi \(\Delta E = Rhc(\frac{1}{n_f^2} - \frac{1}{n_i^2})\); fizik formülü." data-altupdatedat="1754907201000">
Daha sonra, hidrojen atomu için diğer spektral seriler keşfedildi. Örneğin, Lyman serisi, ultraviyole bölgesindeki enerjilere sahip emisyon çizgileri içerir.
<h4>Başvuru</h4>
<ol>
	<li style="font-size:17px">Kotz, J.C., Treichel Jr, P.M., Townsend, J.R. (2012). Kimya ve Kimyasal Reaktivite. Belmont, CA: Brooks/Cole, Cengage Öğrenme.</li>
	<li style="font-size:17px">Silderberg, M.S. (2009). Kimya: Maddenin ve Değişimin Moleküler Doğası. Boston, MA: McGraw Tepesi.</li>
</ol>

Balmer Serisi

Bohr Modeli
Niels Bohr, 1913'te hidrojen atomu için ayrık enerji durumlarının sabit bir elektron yörüngesi ile ilişkili olduğunu tanımlayan bir model önerdi.

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JoVE Lab Manual

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hydrogen emission lines

Hydrogen emission lines show how electrons move between fixed energy levels in the Bohr model. Niels Bohr proposed this model for the hydrogen atom in 1913. In this model, an electron can only occupy certain orbits, and it cannot exist between them.

These energy states are labeled with the quantum number n. The ground state is n = 1. Higher values, such as n = 2, 3, 4, and so on, are excited states. An electron changes state only by absorbing or emitting energy equal to the difference between two levels. A photon with the right energy can move an electron from one orbit to another.

Bohr’s model also links each energy level to a specific amount of potential energy. That value can be calculated with an equation that uses the Rydberg constant, Planck’s constant, and the speed of light. When an electron returns to the ground state or another lower excited state, it releases the extra energy as a photon. The photon energy matches the gap between the two states, so it also determines the wavelength of the emitted light.

Because each atom has its own energy levels, each element gives off its own pattern of light. A mixed sample can produce a continuous spectrum with many wavelengths. A pure sample of one element produces only certain wavelengths. When that light passes through a prism, it appears as separate lines instead of one smooth band.

Hydrogen shows this pattern clearly. Exciting hydrogen atoms requires enough energy to split the H2 molecule, and the extra energy excites the hydrogen electrons to higher levels. When those electrons drop back down, they emit light at wavelengths set by the energy difference between the initial level, n i, and the final level, n f. In pure hydrogen gas, this emission spectrum contains distinct visible, ultraviolet, and infrared lines that are unique to hydrogen.

The visible lines in hydrogen are called the Balmer series. They occur when an electron falls to n = 2 from a higher level. Johann Balmer observed lines at 410.2 nm, 434.1 nm, 486.1 nm, and 656.3 nm, which match transitions from n = 6, 5, 4, and 3 to n = 2. He described these wavelengths with the Balmer formula, where λ is the observed wavelength, C is a constant of 364.50682 nm, n is the lower level, and m is the higher level.

Later, Johannes Rydberg refined this idea using the Rydberg constant. For the Balmer series, the final level n f equals 2. The same relationship, combined with the Bohr model, can be used to calculate the energy change, ΔE, for electron transitions. Other hydrogen spectral series were later identified as well, including the Lyman series, which lies in the ultraviolet region.

Hydrogen Emission Lines

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identifying alcohols

Alcohol Tests for Primary, Secondary, and Tertiary

Alcohol tests can help sort alcohols by structure and reactivity. Alcohols are organic molecules with a hydroxyl group attached to an alkyl or aryl group, written as ROH. If the carbon with the hydroxyl group has one R group, the alcohol is primary. If it has two R groups, it is secondary. If it has three R groups, it is tertiary. Alcohols can also be aromatic when they contain a benzene ring. Phenol is the simplest aromatic alcohol. To identify an alcohol, chemists can use its chemical...

chemistry

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Explore how hydrogen electrons jump between energy levels and produce discrete emission lines, including the visible Balmer series and other hydrogen spectra.

Hydrogen Emission Lines | JoVE K12

Louisiana Student Standards for Science

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Motion And Stability: Forces And Interactions

HS-PS2-6

Tennessee Academic Standards

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Waves and Their Applications in Technologies for Information Transfer

CHEM1.PS4.1

Next Generation Science Standards

Earth and Space Science

Earth’s Place in the Universe

HS-ESS1-2

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South Carolina College and Career Ready Science Standards

Matter and Its Interactions

C-PS1-4

Georgia Standards of Excellence

9-12

SC1.

Light Emission and Electron Movement

Balmer Serisi öğretimine bu 1 dakikalık eğitmen rehberiyle hazırlanın. JoVE Lab Manual üzerindeki Chemistry laboratuvarı için temel hazırlık adımlarını kapsar.

Chemistry içinde Balmer Serisi Eğitmen Hazırlığı - 2.0K+ Görüntülenme | JoVE Lab Manual

4 dakikalık bu öğrenci protokol videosunda Balmer Serisi prosedürlerini adım adım takip edin. JoVE Lab Manual üzerindeki Chemistry koleksiyonunun bir parçasıdır.

Chemistry içinde Balmer Serisi Öğrenci Protokolü - 5.1K+ Görüntülenme | JoVE Lab Manual

The Atomic Theory of Matter

The earliest recorded discussion of the basic structure of matter comes from ancient Greek philosophers. Leucippus and Democritus argued that all matter ...

Subatomic Particles

Dalton was only partially correct about the particles that make up matter. All matter is composed of atoms, and atoms are composed of three smaller ...

Elements: Chemical Symbols and Isotopes

A chemical symbol is an abbreviation used to indicate an element or an atom of an element. For example, the symbol for mercury is Hg. The same symbol is ...

Ions and Ionic Charges

In ordinary chemical reactions, the nucleus &mdash; which contains the protons and neutrons of each atom and thus identifies the element &mdash; remains ...

The Periodic Table

As early chemists discovered more elements, they realized that various elements could be grouped by their similar chemical behaviors. One such grouping ...

Atomic Mass

Atoms &mdash; and the protons, neutrons, and electrons that compose them &mdash; are extremely small. For example, a carbon atom weighs less than 2 ...

Molar Mass

The identity of a substance is defined not only by the types of atoms or ions it contains but by the quantity of each type of atom or ion. For example, ...

Periodic Classification of the Elements

The periodic table arranges atoms based on increasing atomic number so that elements with the same chemical properties recur periodically. When their ...

Types of Chemical Bonds

Chemical bonding theories were pioneered by American chemist Gilbert&#xA0;N. Lewis. He developed a model called the Lewis model to explain the type and ...

Ionic Bonding and Electron Transfer

Ions are atoms or molecules bearing an electrical charge. A cation (a positive ion) forms when a neutral atom loses one or more electrons from its valence ...

The Born-Haber Cycle

Lattice Energy&#xA0;

An ionic compound is stable because of the electrostatic attraction between its positive and negative ions. The lattice energy of a ...

trends-in-lattice-energy-ion-size-and-charge

Trends in Lattice Energy: Ion Size and Charge

An ionic compound is stable because of the electrostatic attraction between its positive and negative ions. The lattice energy of a compound is a measure ...

Covalent Bonding and Lewis Structures

Compared to ionic bonds, which results from the transfer of electrons between metallic and nonmetallic atoms, covalent bonds result from the mutual ...

Electronegativity

Whether a bond is nonpolar or polar covalent is determined by a property of the bonding atoms called electronegativity.&#xA0;

Electronegativity values of ...

bond-polarity-dipole-moment-and-percent-ionic-character

Bond Polarity, Dipole Moment, and Percent Ionic Character

Bond Polarity

The absolute value of the difference in electronegativity (&Delta;EN) of two bonded atoms provides a rough measure of the polarity to be ...

lewis-structures-of-molecular-compounds-and-polyatomic-ions

Lewis Structures of Molecular Compounds and Polyatomic Ions

To draw Lewis structures for complicated molecules and molecular ions, it is helpful to follow a step-by-step procedure as outlined:


	Determine the ...

Bond Energies and Bond Lengths

Stable molecules exist because covalent bonds hold the atoms together. The strength of a covalent bond is measured by the energy required to break it, ...

Bonding in Metals

Metallic bonds are formed between two metal atoms. A simplified model to describe metallic bonding has been developed by Paul Dr&#xFC;de called the ...

Model basic atomic structure and relate an element's atomic structure to its bonding, reactivity, and placement on the Periodic Table.

IPC.7.A

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Physical and Chemical Properties of Matter

The characteristics that enable us to distinguish one substance from another are called properties.

Physical Properties of Matter

A physical property is ...

atomic-radii-and-effective-nuclear-charge

Atomic Radii and Effective Nuclear Charge

The elements in groups of the periodic table exhibit similar chemical behavior. This similarity occurs because the members of a group have the same number ...

Ionic Radii

Ionic radius is the measure used to describe the size of an ion. A cation always has fewer electrons and the same number of protons as the parent atom; it ...

Ionization Energy

The amount of energy required to remove the most loosely bound electron from a gaseous atom in its ground state is called its first ionization energy ...

Electron Affinity

The electron affinity (EA) is the energy change for adding an electron to a gaseous atom to form an anion (negative ion).



This process can be either ...

Alkali Metals

Group 1 elements are soft and shiny metallic solids. They are malleable, ductile, and good conductors of heat and electricity. The melting points of the ...

Halogens

Group 17 elements, known as halogens, are nonmetals. At room temperature, fluorine and chlorine are gases, bromine is a liquid, and iodine a solid. ...

Use patterns within the Periodic Table to predict the relative physical and chemical properties of elements.

IPC.7.B

Science concepts. The student knows that relationships exist between the structure and properties of matter. The student is expected to:

Hydrogen Emission Lines

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