Name: catalyst action in reaction rates
Uploaded: 2020-09-24T15:06:50.000Z
Duration: 2 min 50 s
Channel: JoVE

K12 Standards

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North Carolina K-12 Science Standard Course of Study

9-12

Chemistry

Matter and its Interactions

PS.Chm.5.1

Catalysis

חקר מנגנונים וקינטיקה של תגובות עוזר לחוקרים לטייב את מהירות התגובה. עלייה בטמפרטורה או בריכוז תאיץ את קצב התגובה אבל עלולה גם להוביל לפירוק או לתוצרי לוואי לא רצויים אם יוגברו יתר על המידה. לחלופין, ניתן להוסיף חומר כימי אחר שיאיץ את קצב התגובה מבלי שיעבור שינוי בלתי הפיך או שיתרכב עם חומרים אחרים.חומרים אלה נקראים זרזים ויש להם השפעה על קבוע הקצב בכך שהם משנים את אנרגיית השפעול. זכרו שככל שאנרגיית השפעול גבוהה יותר, כך קצב התגובה יהיה איטי יותר. מכאן שתגובות כימיות רבות, כגון פירוק של מי חמצן, מתרחשות באיטיות.הוספת זרז מפחיתה את אנרגיית השפעול בכך שהיא מוסיפה מנגנון תגובה חליפי ללא השפעה על מצבי האנרגיה של המגיבים והתוצרים. ישנם שני סוגים של זרזים:הומוגניים והטרוגניים. זרז הומוגני מתקיים באותו מצב צבירה כשאר החומרים המגיבים.לדוגמה, מוסיפים נתרן ברומיד לתמיסת מי חמצן כדי להאיץ את תהליך הפירוק שלהם לגז חמצן ולמים. ראשית, יוני הברומיד מגיבים עם מי החמצן בתווך חומצי ויוצרים תמיסה כתומה של ברום מומס ומים. לאחר מכן, הברום המומס ומי החמצן מגיבים זה עם זה ומשחררים יוני ברומיד, כפי שניתן לזהות לפי התמיסה חסרת הצבע.באופן טיפוסי לזרז, יוני הברומיד מאיצים את התגובה אבל לא מתרכבים עם חומרים אחרים ולא מופיעים במשוואה המאוזנת הסופית. זרז הטרוגני מופיע במצב צבירה שונה בהשוואה לחומרים המגיבים. זרזים הטרוגניים מאופיינים בארבעה שלבים טיפוסיים ספיחה, דיפוזיה, תגובה ואפרוש.לדוגמה, תגובת ההידרוגנציה של גז אתן לא רווי לאתן מואצת על ידי חלקיקים קטנטנים של פלדיום מפוזרים על פחם. בדוגמה זו, הזרז הוא במצב מוצק בעוד שהמגיבים הם בצורתם הגזית. במהלך הזירוז ההטרוגני, מולקולות מימן ואתן נספגות על פני השטח של הזרז.הקשר בין מימן למימן נשבר, מה שמאפשר לאטומי המימן לקיים דיפוזיה על פני השטח של הזרז. כשאטומי מימן העוברים דיפוזיה פוגשים מולקולות אתן ספוגות, הן מגיבות ליצירת אתן רווי. כתוצאה מכך, התוצרים משתחררים ומנתרים מפני השטח של המתכת, וכך מותירים את הזרז ללא שינוי.

זרז

<div style="direction:rtl">נוכחות של זרז משפיעה על קצב התגובה הכימית. זרז הוא חומר שיכול להגביר את קצב התגובה מבלי לצרוך אותו במהלך התהליך. ניתן להבין הבנה בסיסית של תפקידו של זרזים במהלך תגובות כימיות מהמושג של מנגנוני תגובה ודיאגרמות אנרגיה. <img alt="תמונה 1" src="/files/ftp_upload/11383/11383_Image_1.png" style="text-align: center; height: 350px;"> התמונה המאוירת מייצגת את דיאגרמות התגובה עבור תהליך כימי אנדותרמי המתקדם בהיעדר (עקומה אדומה) ונוכחות (עקומה כחולה) של זרז. שתי העקומות מייצגות את אותה תגובה כוללת - הן מתחילות ומסתיימות באותן אנרגיות. (במקרה זה, לתוצרים יש יותר אנרגיה ממגיבים. לפיכך, התגובה היא אנדותרמית). עם זאת, מנגנוני התגובה שלהם שונים. התגובה הבלתי מזורזת ממשיכה במנגנון חד-שלבי (עם רק מצב מעבר אחד שנצפה). לעומת זאת, התגובה המזוזרת עוקבת אחר מנגנון דו-שלבי (נצפים שני מצבי מעבר) עם אנרגיית הפעלה פחותה במיוחד. הבדל זה בנתיבי התגובה ממחיש את תפקידו של הזרז במתן מנגנון תגובה חלופי עם אנרגיית הפעלה נמוכה יותר, ובכך להאיץ את התגובות. מנגנון התגובה המזורזת אינו צריך לכלול מספר גבוה יותר של שלבים אלמנטריים מאשר המנגנון הבלתי מזורז. עם זאת, עליו לספק נתיב תגובה חלופי ששלב קביעת הקצב שלו מהיר יותר (עם אנרגיית Ea או הפעלה נמוכה יותר). תגובה מזורזת עשויה להיות מסווגת כהומוגנית או הטרוגנית, בהתבסס על המצבים הפיזיקליים שבהם קיימים זרזים ומגיבים במהלך התהליך המזרז. זרז הומוגני בזרז הומוגני, הזרז קיים באותו שלב כמו המגיבים - מוצק, נוזל או גז. במהלך התהליך, הזרז יוצר אינטרקציה עם המגיב ליצירת חומר ביניים, אשר לאחר מכן מתפרק או מגיב עם מגיב אחר בשלב אחד או יותר כדי ליצור מחדש את הזרז המקורי וליצור את התוצר הסופי. דוגמה לזרז הומוגני הוא התהליך הכימי הכרוך בפירוק האוזון המתרחש באטמוספירה העליונה של כדור הארץ. אוזון הוא מולקולה לא יציבה יחסית שמתפרקת כדי להניב חמצן דו-אטומי. תגובת פירוק זו תואמת את המנגנון הדו-שלבי הבא: <img alt="Eq1" src="/files/ftp_upload/11383/11383_Equation_1.png" style="text-align: center; height: 75px;"> חומרים רבים יכולים לזרז את פירוק האוזון. לדוגמה, ההערכה היא שהפירוק המזורז של אוזון מתרחש באמצעות מנגנון שלושת השלבים הבא: <img alt="Eq2" src="/files/ftp_upload/11383/11383_Equation_2.png" style="text-align: center; height: 115px;"> עם זאת, התגובה הכוללת זהה הן למנגנון הבלתי מזורז בן שני השלבים והן למנגנון התלת-שלבי מזורז NO: <img alt="Eq3" src="/files/ftp_upload/11383/11383_Equation_3.png" style="text-align: center; height: 50px;"> בתגובה מזורזת, שימו לב ש-NO הוא מגיב בשלב הראשון של המנגנון ותוצר בשלב האחרון. זוהי תכונה אופיינית נוספת של זרז: למרות שהוא משתתף בתגובה הכימית, הוא אינו נצרך על ידי התגובה. בנוסף, בזרז הומוגני זה, גם המגיב וגם הזרז קיימים בשלב גז. זרז הטרוגני בזרז הטרוגני, הזרז קיים בשלב שונה (בדרך כלל מוצק) מאשר המגיבים. זרזים כאלה פועלים בדרך כלל על ידי יצירת משטח פעיל שעליו יכולה להתרחש תגובה. תגובות גז ושלב נוזלי המזורזות על ידי זרזים הטרוגניים מתרחשות על פני השטח של הזרז ולא בתוך שלב הגז או הנוזל. זרז הטרוגני כולל בדרך כלל את התהליכים הבאים: <ol style="padding-right: 35px; margin: 0;"> <li style="text-align: right;">ספיחה של המגיב(ים) על פני השטח של הזרז</li> <li style="text-align: right;">הפעלת המגיב/ים הנספחים</li> <li style="text-align: right;">התגובה של המגיב/ים הנספגים</li> <li style="text-align: right;">ספיגה של מוצר(ים) מפני השטח של הזרז</li> </ol> <img alt="תמונה 2" src="/files/ftp_upload/11383/11383_Image_2.png" style="text-align: center; height: 250px;"> התמונה המאוירת מייצגת את מנגנון התגובה הכולל זרז הטרוגני של גז אתן ומימן על משטח ניקל מוצק, ויוצרים גז אתאן (C2H4 + H2 ⟶ C2H6): (א) מימן סופח על פני הניקל. במהלך התהליך מתפרקים קשרי מימן-מימן ליצירת קשרי ניקל-מימן. (ב) אתן נספג גם על פני הניקל על ידי שבירת קשר הפחמן-פחמן פי ויצירת קשרי ניקל-פחמן. (ג) אטומי מימן מתפזרים על פני השטח ויוצרים קשרי פחמן-מימן חדשים כאשר הם מתנגשים ויוצרים אתאן (C2H6). (ד) מולקולות אתאן נספגות ממשטח הניקל. זרז הטרוגני משמש לייצור תעשייתי של מוצרים כימיים כגון אמוניה, חומצה חנקתית, חומצה גופרתית ומתנול. זרזים הטרוגניים משמשים גם בממירים קטליטיים הנמצאים ברוב המכוניות המונעות בבנזין. טקסט זה מותאם מ <a href="https://openstax.org/books/chemistry-2e/pages/12-7-catalysis">Openstax, Chemistry 2e, Section 12.7: Catalysis</a>.</div>

נוכחותו של זרז משפיעה על קצב התגובה הכימית. זרז הוא חומר שיכול להגביר את קצב התגובה מבלי להיות נצרך ...

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Chemical Kinetics

קינטיקה כימית

KEY TERMS AND CONCEPTS

מונחים ומושגים מרכזיים

catalyst action in reaction rates

Catalysts change the rate of a chemical reaction by giving it a faster path. A catalyst increases reaction rate without being consumed during the process. Its effect is often explained with reaction mechanisms and energy diagrams.

For an endothermic reaction, the reactants and products start and end at the same energies in both cases. The uncatalyzed path is a one-step mechanism with one transition state. The catalyzed path follows a different mechanism with two transition states and a lower activation energy, or Ea. The lower rate-determining barrier is what makes the reaction faster.

Catalytic reactions are often grouped as homogeneous or heterogeneous. In homogeneous catalysis, the catalyst and reactants are in the same phase, which may be solid, liquid, or gas. The catalyst reacts with the reactant to form an intermediate, and that intermediate then breaks down or reacts again to form the product and regenerate the catalyst.

A good example of homogeneous catalysis is ozone decomposition in the upper atmosphere. Ozone breaks down to form diatomic oxygen, and nitric oxide can catalyze that process through a three-step mechanism. In this reaction, NO appears as a reactant in the first step and a product in the last step, which shows that it participates in the reaction but is not used up. Here, both the reactant and the catalyst are gases.

In heterogeneous catalysis, the catalyst is in a different phase from the reactants, usually a solid. These reactions happen on the catalyst surface. They typically include adsorption of reactants, activation on the surface, reaction of the adsorbed molecules, and desorption of the products.

The nickel-catalyzed reaction of ethene and hydrogen to form ethane shows this surface process. Hydrogen first adsorbs on nickel, and the H-H bond breaks to form nickel-hydrogen bonds. Ethene also adsorbs as its carbon-carbon pi bond breaks and nickel-carbon bonds form. Hydrogen atoms then move across the surface and make new carbon-hydrogen bonds, and the ethane product desorbs from the nickel surface.

Heterogeneous catalysts are important in industry. They help make ammonia, nitric acid, sulfuric acid, and methanol. They are also used in catalytic converters in most gasoline-powered cars.

Catalyst Action in Reaction Rates

reaction rate

Measuring Reaction Rates

Measuring reaction rates shows how fast reactants are used up or products are formed over time. The rate of reaction is the change in the amount of a reactant or product per unit time. Because of that, scientists measure how a property changes as the reaction proceeds and connect that change to reactant or product amounts. For reactions that make or use a gas, the rate can be followed by changes in volume or pressure. A rate expression is the mathematical way to write how concentration changes...

measuring reaction rates

Tracking Reaction Kinetics with Light and Pressure

Reaction kinetics can be tracked with polarimetry, spectrometry, and pressure measurements. These methods let scientists follow a reaction without disturbing the sample. They also help determine how reactant or product concentrations change over time. Polarimetry is used for optically active substances. These substances rotate the plane of polarized light, which is called optical rotation. The effect comes from molecular structure. Normal monochromatic light is unpolarized, but after it passes...

concentration and rate law

Reaction Order from Concentration

Reaction order from concentration shows how reactant amounts affect reaction rate. Rate laws, also called differential rate laws or rate equations, are mathematical expressions that connect reaction rate with the concentrations of reactants. For a generic reaction a A + b B → products, the rate law can be written using the reactant concentrations [A] and [B] and a rate constant k. In a rate law, k is the rate constant for one specific reaction at one specific temperature. The exponents m and n...

determining order of reaction

Finding Rate Law from Initial Rates

Rate laws connect the speed of a chemical reaction to the concentration of its reactants. The rate constant, k, and the reaction orders are not taken from the chemical equation. They are found experimentally by watching how the rate changes when the reactant concentrations change. One common way to do this is the method of initial rates. In this method, several trials are run with different starting concentrations. The measured rates are then compared to determine the reaction orders and,...

the integrated rate law: the dependence of concentration on time

the-integrated-rate-law-the-dependence-of-concentration-on-time

Reading Reaction Progress with Integrated Laws

Integrated rate laws connect reaction concentration to time. They help show how much reactant or product is present after a certain period. They can also help estimate how long a reaction must run to reach a given extent. A common use is finding how long radioactive material must be stored before its radioactivity drops to a safe level. These equations come from the differential rate law after it is integrated with respect to time. For a first-order reaction, where rate = k[A], the integrated...

half-life of a reaction

Reaction Half-Life in Kinetics

Reaction half-life is the time needed for half of a reactant to be consumed. After each half-life, half of the remaining reactant is used up. A hydrogen peroxide decomposition example shows this pattern clearly. The concentration drops from 1.000 M to 0.500 M in the first 6.00 hours, then to 0.250 M in the next 6.00 hours, and then to 0.125 M in the third period. Each later 6.00-hour interval removes half of what is left. For first-order reactions, the half-life does not depend on the reactant...

temperature dependence on reaction rate

Collision Theory and Reaction Speed

Collision theory explains why reaction speed depends on how particles collide. Atoms, molecules, or ions must come close together before they can react. The theory says the reaction rate depends on the collision rate, the orientation of the colliding species, and whether the collision has enough energy for bonds to change. A gas-phase reaction between carbon monoxide and oxygen shows why orientation matters. The molecules can collide in more than one way. If the oxygen side of carbon monoxide...

arrhenius plots

Determining Activation Energy from Temperature

The Arrhenius equation links activation energy and the rate constant, k, for chemical reactions. It is written as k = Ae−Ea/RT. In this equation, R is the ideal gas constant with a value of 8.314 J/mol·K, T is the temperature on the kelvin scale, Ea is the activation energy in J/mole, e is the constant 2.7183, and A is the frequency factor. The frequency factor depends on collision frequency and the orientation of reacting molecules. Experimental kinetic data can be used to find the activation...

reaction mechanisms

Elementary Steps in Reaction Mechanisms

Chemical reactions can happen in steps, and a balanced equation does not show the full path at the molecular level. A reaction mechanism, also called a reaction path, gives the step-by-step process that explains how reactants become products. The decomposition of ozone is one example of a reaction that can be described by a sequence of steps. Each step in a mechanism is an elementary reaction. These elementary reactions happen in order, and when they are added together, they give the balanced...

rate-determining steps

Reaction Bottlenecks in Chemical Kinetics

Reaction bottlenecks help explain rate-determining steps in multistep reaction mechanisms. In a mechanism with several elementary steps, one step is often much slower than the others. That slowest step is called the rate-limiting step, or rate-determining step. A reaction cannot move faster than its slowest step, so this step controls the overall reaction rate. The idea is like traffic on a four-lane freeway with one lane closed. Cars can only move as fast as the bottleneck allows. In the same...

catalysis

Catalysts change the rate of a chemical reaction by giving it a faster path. A catalyst increases reaction rate without being consumed during the process. Its effect is often explained with reaction mechanisms and energy diagrams. For an endothermic reaction, the reactants and products start and end at the same energies in both cases. The uncatalyzed path is a one-step mechanism with one transition state. The catalyzed path follows a different mechanism with two transition states and a lower...

enzymes

Enzyme Action and Inhibition

Enzymes are biological catalysts that speed up many reactions in living organisms. They help control cellular metabolism by lowering the activation energy needed for biochemical reactions. When activation energy drops, reaction rates can increase. Enzyme problems can also lead to serious disease. A genetic abnormality that causes G6PD, or glucose-6-phosphate dehydrogenase, deficiency can disrupt the pathway that supplies NADPH to cells. In red blood cells, this can reduce glutathione and...

key terms and concepts

Explore how catalysts speed up reactions by lowering activation energy, with clear examples of homogeneous and heterogeneous catalysis for high school chemistry.

Catalyst Action in Reaction Rates | JoVE K12

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Physical Science

Chemical Reactions

3.2.9-12.D

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New York State Science Learning Standards

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Catalysts in Chemical Reactions

Scientific Laws and Theories

Scientific Laws

In science, a law is defined as a concise, verbal or mathematical, statement that summarizes a vast number of experimental observations. ...

The Scientific Method

Chemistry is an empirical science. Scientists often pose questions to understand the chemistry in everyday life and seek answers to these questions. To ...

Classifying Matter by State

Chemistry is the study of matter and the changes it undergoes. Matter is anything that has mass and occupies space. Matter is all around us; the air, ...

Classifying Matter by Composition

Matter: Pure Substances and Mixtures
According to its composition, the matter can be classified into two broad categories &mdash; pure substances and ...

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 ...

Use models to explain how the scientific understanding of atomic structure has evolved.

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Radioactivity and Nuclear Equations

Nuclear chemistry is the study of reactions that involve changes in nuclear structure. The nucleus of an atom is composed of protons and, except for ...

Types of Radioactivity

The most common types of radioactivity are &#945; decay, &#946; decay, &#947; decay, neutron emission, and electron capture.
Alpha (&#945;) decay is the ...

Nuclear Stability

Protons and neutrons, collectively called nucleons, are packed together tightly in a nucleus. With a radius of about 10&#8722;15 meters, a nucleus is ...

Nuclear Binding Energy

The difference between the calculated and experimentally measured masses is known as the mass defect of the atom. In the case of helium-4, the mass defect ...

Radioactive Decay and Radiometric Dating

Radioactivity is a spontaneous disintegration of an unstable nuclide and is a random process, as all the nuclei in the sample do not decay simultaneously. ...

Nuclear Fission

Many heavier elements with smaller binding energies per nucleon can decompose into more stable elements that have intermediate mass numbers and larger ...

Nuclear Power

Controlled nuclear fission reactions are used to generate electricity. Any nuclear reactor that produces power via the fission of uranium or plutonium by ...

Nuclear Fusion

The process of converting very light nuclei into heavier nuclei is also accompanied by the conversion of mass into large amounts of energy, a process ...

Nuclear Transmutation

Nuclear transmutation is the conversion of one nuclide into another. It can occur by the radioactive decay of a nucleus, or the reaction of a nucleus with ...

Use models to compare nuclear reactions including alpha decay, beta decay and gamma decay; nuclear fusion and nuclear fission.

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Atomic Orbitals

An atomic orbital represents the three-dimensional regions in an atom where an electron has the highest probability to reside. The radial distribution ...

The Pauli Exclusion Principle

The arrangement of electrons in the orbitals of an atom is called its electron configuration. We describe an electron configuration with a symbol that ...

The Energies of Atomic Orbitals

In an atom, the negatively charged electrons are attracted to the positively charged nucleus. In a multielectron atom, electron-electron repulsions are ...

The Aufbau Principle and Hund's Rule

To determine the electron configuration for any particular atom, we can build the structures in the order of atomic numbers. Beginning with hydrogen, and ...

electron-configuration-of-multielectron-atoms

Electron Configuration of Multielectron Atoms

The alkali metal sodium (atomic number 11) has one more electron than the neon atom. This electron must go into the lowest-energy subshell available, the ...

Use models to explain how electrons are distributed in atoms.

PS.Chm.1.3

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 ...

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, ...

Use the Periodic Table as a model to predict the relative properties of elements based on the pattern of valence electrons in the outermost energy levels of atoms.

PS.Chm.2.1

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 ...

Construct an explanation to infer the atomic size, reactivity, electronegativity, and ionization energy of an element based on its position in the Periodic Table.

PS.Chm.2.2

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 ...

Lewis Symbols and the Octet Rule

Chemical bonds are complex interactions between two or more atoms or ions, which reduce the potential energy of the molecule. Gilbert N. Lewis developed a ...

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 ...

Resonance

The Lewis structure of a nitrite anion (NO2&minus;) may actually be drawn in two different ways, distinguished by the locations of the N-O and N=O ...

Formal Charges

In some cases, there are seemingly more than one valid Lewis structures for molecules and polyatomic ions. The concept of formal charges can be used to ...

Exceptions to the Octet Rule

Many covalent molecules have central atoms that do not have eight electrons in their Lewis structures. These molecules fall into three categories:


	...

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, ...

Analyze and interpret data to explain the mechanisms and properties of the two main types of intramolecular (ionic and covalent) bonds.

PS.Chm.3.1

molecular-comparison-of-gases-liquids-and-solids

Molecular Comparison of Gases, Liquids, and Solids

Particles in a solid are tightly packed together (fixed shape) and often arranged in a regular pattern; in a liquid, they are close together with no ...

Intermolecular vs Intramolecular Forces

Intermolecular forces (IMF) are electrostatic attractions arising from charge-charge interactions between molecules. The strength of the intermolecular ...

Construct an explanation to summarize the influences intermolecular forces have on the properties of chemical compounds.

PS.Chm.3.2

Analyze the structure of atoms and isotopes.

Catalyst Action in Reaction Rates

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