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

تظهر الذرات والجزيئات سلوكا مثيرا للاهتمام عندما تمتص الطاقة وتطلقها. توجد الإلكترونات في الذرة تقليديا في أدنى حالة طاقة لها ، تسمى الحالة الأرضية ، وتسمى n تساوي واحدا. ومع ذلك ، عندما تمتص الذرة الطاقة ، تصبح الإلكترونات متحمسة وتنتقل إلى مستوى طاقة أعلى. عندما تسترخي الإلكترونات إما إلى حالة طاقة أقل أو إلى الحالة الأرضية ، يتم إطلاق الطاقة الزائدة كضوء منبعث. 
قد تكون على دراية بحالات الطاقة هذه ، كما هو موضح في نموذج بور ، الذي يصف الذرة على أنها نواة بها إلكترونات تدور في الأصداف أو المدارات. هذه الأصداف هي نفس مستويات الطاقة ويتم تصنيفها ب n. يعتمد الطول الموجي للضوء المنبعث على الفرق بين مستويات الطاقة العالية والمنخفضة. ينتج الضوء المنبعث من الطاقة العالية عن استرخاء الإلكترونات من مستوى طاقة أعلى ، وينتج الضوء المنبعث من الطاقة المنخفضة عن استرخاء الإلكترونات من مستوى طاقة أقل. 
طيف الانبعاث هو مقياس للإشعاع المنبعث عبر مجموعة من الأطوال الموجية. مع الأنواع الأولية النقية ، يظهر سلوك الانبعاث كخطوط ذات أطوال موجية محددة بدلا من طيف واسع. نظرا لأن الذرات المختلفة لها مستويات طاقة مختلفة ، فإن هذه الخطوط الطيفية تختلف من عنصر إلى آخر وتعتمد على التحولات التي تقوم بها هذه الإلكترونات بين حالات الطاقة عند الإثارة. على سبيل المثال ، هناك ستة سلاسل مسماة من الخطوط الطيفية للهيدروجين ، إحداها هي سلسلة Balmer. 
تحدث سلسلة Balmer من الخطوط الطيفية عندما تنتقل الإلكترونات من مستوى طاقة أعلى من n = 3 إلى n = 2. يظهر طيف الضوء المرئي لسلسلة Balmer كخطوط طيفية عند 410 و 434 و 486 و 656 نانومتر. خط h alpha هو الخط الأحمر عند 656 نانومتر ويحدث بسبب الانتقال من n = 3 إلى n = 2. تتوافق الخطوط السماوية والأزرق والبنفسجي مع انتقالات مستوى الطاقة من n = 4 و 5 و 6 ، على التوالي ، إلى n = 2. يمكن قياس الخطوط الطيفية الإضافية خارج النطاق المرئي. 
قام يوهان بالمر بتحديد الخطوط المرئية باستخدام صيغة بالمر. هنا ، لامدا هو الطول الموجي المرصود ، c ثابت ، n هو مستوى الطاقة الأدنى لاثنين ، و m هو مستوى الطاقة الأعلى. يعطينا الجمع بين معادلة بالمر ونموذج بور معادلة ريدبيرغ ، التي تصف الخطوط الطيفية للعديد من العناصر المختلفة. في هذه المعادلة ، لامدا هو الطول الموجي المسجل ، و R H هو ثابت Rydberg. تمثل المستويات الأولية المميزة ب n-initial مستوى الطاقة الأعلى الذي تثيره الإلكترونات و n نهائي هو مستوى الطاقة الأدنى الذي تسترخي إليه الإلكترونات مرة أخرى. بالنسبة لسلسلة Balmer ، n final = 2. 
في هذا المختبر ، ستقوم بقياس ومراقبة أطياف انبعاث الهيدروجين والهيليوم والنيون واستخدام معادلة ريدبيرغ لتحديد موقع الخطوط الطيفية.

سلسلة بالمر

نموذج بور
اقترح نيلز بور نموذجا لذرة الهيدروجين في عام 1913 يصف أن حالات الطاقة المنفصلة مرتبطة بمدار إلكترون ثابت حول النواة. الأهم من ذلك ، لا يمكن للذرة تفريغ الطاقة بينما تكون إلكتروناتها في حالة ثابتة. لا يمكن للإلكترون أن ينبعث منه طاقة إلا عن طريق تغيير حالات الطاقة. لتغيير حالات الطاقة ، يجب أن ينتقل الإلكترون من مدار إلى آخر إما عن طريق امتصاص الطاقة أو انبعاثها. لا يمكن أن يحدث هذا التغيير إلا إذا كانت الطاقة الممتصة أو المنبعثة تساوي الفرق بين الحالتين. لا يمكن أن توجد الإلكترونات بين المدارات. 
يستخدم الرقم الكمي ، n ، لتسمية حالات الطاقة المختلفة. أدنى حالة طاقة هي الحالة الأرضية ، والتي تساوي n واحدا. يتم تسمية الحالات المثارة n تساوي 2 و 3 و 4 وهكذا. عندما يمتص إلكترون في الحالة الأرضية فوتونا تساوي طاقته الفرق بين الحالة الأرضية والثانية ، يصبح الإلكترون متحمسا وينتقل من الحالة الأرضية إلى الحالة المثارة n = 2. إذا كانت طاقة الفوتون تساوي الفرق بين الحالة الأرضية والحالة الثالثة ، فإن الإلكترون ينتقل إلى الحالة n = 3. 
وفقا لنموذج بور ، يمكن حساب الطاقة الكامنة للإلكترون في المستوى n باستخدام المعادلة التالية:
<img src="/CDNSource/lm/labs/54/54_Concepts_1.jpg" alt="صيغة مستوى طاقة نموذج بور ، En = -Rhc / n² ، المتعلقة بتحولات الإلكترون ، المعادلة." data-altupdatedat="1754907201000" data-alt="Bohr model energy equation \(E_n=-\frac{Rhc}{n^2}\), quantum mechanics concept.">
 حيث En هي الطاقة الكامنة، R هو ثابت Rydberg (1.0974 × 107 m-1)، h هو ثابت بلانك (6.62607004 × 10-34} m2·kg/s)، و c هي سرعة الضوء (~ 3 × 108 m/s). يمكن للإلكترونات أيضا أن تعود تلقائيا إلى الحالة الأرضية أو أي حالة أخرى مثارة أقل. عندما يحدث هذا ، يتم إطلاق الطاقة الزائدة على شكل فوتون منبعث. طاقة الفوتون تساوي فرق الطاقة بين حالات الطاقة الأعلى والمنخفضة. هذه الطاقة تتوافق مع الأطوال الموجية للضوء. نظرا لأن كل نوع من أنواع الذرات له مستويات طاقة مختلفة ، فإن الضوء المنبعث من كل انتقال يختلف لكل ذرة. بالنسبة لعينة من الجزيئات المختلطة ، يحتوي الضوء المنبعث على مجموعة من الأطوال الموجية فيما يسمى الطيف المستمر. بالنسبة للعينة التي تحتوي على ذرات من عنصر واحد ، يحتوي الضوء المنبعث على أطوال موجية معينة فقط ، والتي يمكن رؤيتها كخطوط منفصلة بمجرد فصلها بواسطة منشور. 
<h4>ذرة الهيدروجين</h4>
بالنظر على وجه التحديد إلى ذرة الهيدروجين ، فإن إثارة إلكتروناتها تتطلب امتصاص طاقة كافية لتقسيم الرابطة في جزيء ثنائي الذرة H2. نظرا لاستخدام طاقة لتقسيم الجزيء أكثر من اللازم ، فإن الإلكترونات الموجودة في ذرة الهيدروجين تمتص الطاقة الزائدة وتتحمس إلى مستوى طاقة أعلى. عندما تعود الإلكترونات تلقائيا إلى مستوى طاقة أقل ، ينبعث الضوء ، وهو ما يتوافق مع فرق الطاقة بين المستوى المثار والمستوى الأدنى. 
عند مناقشة انبعاث الطاقة ، يعتبر مستوى الطاقة الأعلى هو المستوى الأولي ، أو n i ، بينما يعتبر المستوى الأدنى هو المستوى النهائي ، أو nf }. تعتمد الأطوال الموجية للضوء المنبعث في النهاية على فرق الطاقة بين المستويين. 
في عينة نقية من غاز الهيدروجين ، يظهر طيف الانبعاث كخطوط مميزة من الأطوال الموجية المنفصلة الخاصة بعنصر الهيدروجين. تقع بعض هذه الخطوط في النطاق المرئي للطيف الكهرومغناطيسي ، بينما يقع بعضها في نطاق الأشعة فوق البنفسجية أو الأشعة تحت الحمراء. 
<h4>سلسلة بالمر </h4>
تسمى سلسلة الخطوط المرئية في طيف ذرة الهيدروجين سلسلة Balmer. تحدث هذه السلسلة من خطوط الانبعاث الطيفية عندما ينتقل الإلكترون من مستوى طاقة عالية إلى مستوى طاقة أقل من n = 2. لاحظ يوهان بالمر هذه الخطوط الطيفية عند 410.2 نانومتر و 434.1 نانومتر و 486.1 نانومتر و 656.3 نانومتر ، والتي تتوافق مع التحولات من مستويات الطاقة n = 6 و n = 5 و n = 4 و n = 3 إلى مستوى n = 2 ، على التوالي. 
كان بالمر قادرا على ربط هذه الأطوال الموجية للضوء المنبعث باستخدام صيغة بالمر. 
<img src="/CDNSource/lm/labs/54/54_Concepts_2.jpg" alt="صيغة حساب الطول الموجي λ = C (m² / (m²-n²)) ، معادلة تحليل التحليل الطيفي." data-altupdatedat="1754907201000" data-alt="Wavelength formula λ=C(m²/(m²−n²)); physics equation; diagram for wave analysis.">
هنا ، λ هو الطول الموجي المرصود ، C ثابت (364.50682 نانومتر) ، n هو مستوى الطاقة الأدنى بقيمة 2 ، و m هو مستوى الطاقة الأعلى ، الذي له قيمة أكبر من 3. ثم تم تنقيح هذه الملاحظة بواسطة يوهانس ريدبيرغ ، حيث R هو ثابت Rydberg. 
<img src="/CDNSource/lm/labs/54/54_Concepts_3.jpg" alt="معادلة صيغة ريدبيرغ. يحسب الخطوط الطيفية في التحليل الطيفي الذري." data-altupdatedat="1754907201000" data-alt="Rydberg formula for spectral lines, equation, physics, spectroscopy calculation.">
تذكر أن هذه المعادلة تصف الضوء المنبعث ، لذلك يعتبر مستوى الطاقة الأعلى هو المستوى الأولي ، أو n i ، بينما يعتبر المستوى الأدنى هو المستوى النهائي ، أو nf . في حالة سلسلة Balmer ، فإن nf يساوي 2. تم دمج هذه المعادلة مع نموذج بور لحساب الطاقة اللازمة لتحريك الإلكترون بين مستويات الطاقة الأولية والنهائية ، ΔE. 
<img src="/CDNSource/lm/labs/54/54_Concepts_4.jpg" alt="معادلة انتقال مستوى الطاقة \(\Delta E = Rhc(\frac{1}{n_f^2} - \frac{1}{n_i^2})\); صيغة الفيزياء." data-altupdatedat="1754907201000" data-alt="Energy change formula, ΔE=Rhc(1/nf²-1/ni²), spectral transition equation, quantum physics.">
في وقت لاحق ، تم اكتشاف سلسلة طيفية أخرى لذرة الهيدروجين. على سبيل المثال ، تحتوي سلسلة Lyman على خطوط انبعاث مع طاقات في منطقة الأشعة فوق البنفسجية. 
<h4>المراجع</h4>
<ol>
	<li style="font-size:17px">كوتز ، جي سي ، تريتشيل جونيور ، بي إم ، تاونسند ، جي آر (2012). الكيمياء والتفاعل الكيميائي. بلمونت ، كاليفورنيا: بروكس / كول ، Cengage Learning. </li>
	<li style="font-size:17px">سيلدربيرج ، MS (2009). الكيمياء: الطبيعة الجزيئية للمادة والتغيير. بوسطن ، ماساتشوستس: ماكجرو هيل. </li>
</ol>

نموذج بور
اقترح نيلز بور نموذجا لذرة الهيدروجين في عام 1913 يصف حالات الطاقة المنفصلة المرتبطة بمدار إلكترون ثابت ...

Education

JoVE Lab Manual

Chemistry

الكيمياء

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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recrystallization

Purifying Crystals by Solubility

Purifying crystals by solubility is a key organic chemistry technique. Recrystallization uses differences in solubility to separate a desired solid product from starting materials, solvent, and impurities. It is one of the three standard purification methods, along with distillation and extraction. Solubility is the maximum amount of a substance that can dissolve in a fixed volume of solvent at a given temperature. Different solutes dissolve in different solvents, and their behavior can vary...

extraction

Separating Mixtures with Solvent Extraction

Solvent extraction is a common way to separate and isolate a target compound in organic chemistry. In this process, a solute moves from one phase to another so it can be separated from unreacted starting materials or impurities. Extraction is also useful when a product is dissolved in a reaction solvent that is hard to remove by evaporation, such as a solvent with a high boiling point. There are three main types of extraction. In solid-liquid extraction, the solute moves from a solid phase...

simple distillation

Separating Liquids by Boiling Point

Separating liquids by boiling point is the goal of distillation. A miscible mixture contains liquids that mix evenly, and it can be heated so that the more volatile liquid evaporates first. Volatility is a liquid’s tendency to vaporize, and boiling begins when bubbles form in the liquid phase. In a closed container, liquid and vapor can reach equilibrium, which means the rate of vaporization equals the rate of condensation. The pressure from the vapor above the liquid is called vapor pressure.

steam distillation

Steam Distillation and Low-Boiling Separation

Steam distillation is a separation method for temperature-sensitive organic compounds. It works best when the organic compound is immiscible in water, meaning the two liquids do not mix. The method helps remove the organic molecule from a non-volatile contaminant without using the higher temperatures needed for many other separations. In steam distillation, the immiscible mixture is heated until both water and the volatile organic compound distill together. The vapor rises to a condenser,...

thin-layer chromatography

TLC Separation by Polarity

Thin-layer chromatography (TLC) separates compounds in a mixture by polarity. It uses the same basic parts as other chromatography methods: a stationary phase, a mobile phase, and the solute. In TLC, the stationary phase is a thin coating on a plate instead of material packed into a column. The stationary phase in most TLC systems is polar silica gel, a form of silicon dioxide. Its surface has OH groups that can form hydrogen bonds. The sample is first spotted on a pencil start line with a...

column chromatography

Separating Mixtures by Polarity

Column chromatography separates compounds in an organic chemistry lab by using differences in physical properties. It is especially useful for microscale separations when less than 10 grams of material is available for analysis. The method can separate a mixture based on solubility, polarity, hydrophobicity, size, and charge. Any chromatography system has three main parts: the stationary phase, the mobile phase, and the sample mixture. In column chromatography, the stationary phase is usually...

hydrolysis of an ester

Soap Formation from Triglycerides

Triglycerides are lipids made of a glycerol backbone linked to three fatty acids. They are common in vegetable oils and animal fats. Plant lipids are the basis of vegetable oils, while animal lipids are used as lard or general sources of fats. A fatty acid has a long carbon chain, usually between 12 and 20 carbons, with a weak organic acid at one end. Some fatty acids contain double bonds. These are unsaturated fats. The double bond usually gives the chain a bent, cis shape. As a result,...

synthesis of luminol

Luminol Chemiluminescence in Forensics

Luminol chemiluminescence shows how a chemical reaction can produce light and help with blood detection. Chemical reactions may be endothermic or exothermic, depending on whether they absorb or release heat as reactants become products. The enthalpy of a reaction is the energy difference between reactants and products, or ΔH. A positive ΔH means the reaction is endothermic. A negative ΔH means it is exothermic. Many reactions do not happen in a single step. They can pass through intermediates...

esterification

Ester Formation and Everyday Fragrances

Esters are organic compounds with a carbonyl group attached to an oxygen that connects to another alkyl or aryl group. Their general formula is RCOOR'. They are often made by reacting a carboxylic acid with an alcohol in an esterification reaction. In this process, the hydroxyl group of the acid is replaced by an alkyl or aryl group. Many simple esters have familiar fruit and flower smells because their structures are small and less complex. Formic acid and methanol can combine to form methyl...

identification of unknown aldehydes and ketones

identification-of-unknown-aldehydes-and-ketones

Carbonyl Tests for Aldehydes and Ketones

Aldehydes and ketones are carbonyl compounds, which means they contain a C=O functional group. A ketone has two alkyl or aryl groups attached to the carbonyl carbon. Acetone is the simplest ketone, with two methyl groups. An aldehyde is similar, but it has at least one hydrogen attached to the carbonyl carbon. Formaldehyde is the simplest aldehyde, and acetaldehyde has one hydrogen and one methyl group. The carbonyl carbon in both aldehydes and ketones is electrophilic because the oxygen atom...

uv-vis spectroscopy of dyes

How Dyes Absorb Visible Light

Dyes absorb visible light because their molecular structure lets them interact with specific wavelengths. When light hits a substance, some light is absorbed and the rest is reflected or transmitted. The color we see depends on the wavelength that is reflected. A blue substance reflects blue light, around 430 to 480 nm, and absorbs the complementary orange region, around 590 to 630 nm. Compounds that do not absorb in the visible range appear colorless to the human eye. Light also has energy and...

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

Comprehensive, curriculum-focused videos for both instructors and students in introductory chemistry lab courses.

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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

motion-and-stability-forces-and-interactions

Motion And Stability: Forces And Interactions

HS-PS2-6

Tennessee Academic Standards

waves-and-their-applications-in-technologies-for-information-transfer

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

south-carolina-college-and-career-ready-science-standards

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

استعد لتدريس سلسلة بالمر من خلال هذا الدليل الإرشادي للمدرسين لمدة 1 دقيقة. يغطي خطوات التحضير الأساسية لمختبر Chemistry على JoVE Lab Manual.

تحضير المدرّس لـ سلسلة بالمر في Chemistry - أكثر من 2.0K مشاهدة | JoVE Lab Manual

اتبع إجراءات سلسلة بالمر خطوة بخطوة في فيديو بروتوكول الطالب هذا لمدة 4 دقيقة. جزء من مجموعة Chemistry على JoVE Lab Manual.

بروتوكول الطالب لـ سلسلة بالمر في Chemistry - أكثر من 5.1K مشاهدة | 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

physical-and-chemical-properties-of-matter

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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