Name: how acids and bases form ions
Uploaded: 2020-09-03T13:38:26.000Z
Duration: 3 min 26 s
Channel: JoVE

K12 Standards

north-carolina-k-12-science-standard-course-of-study

North Carolina K-12 Science Standard Course of Study

9-12

Physical Science

Matter and its Interactions

PS.PSc.2.4

Acids, Bases and Neutralization Reactions

Lo stomaco umano è un organo muscolare contenente succhi gastrici, compreso l'acido cloridrico, che aiutano a digerire il cibo. Alcuni tipi di alimenti aumentano i livelli di acidità del nostro stomaco, provocando il reflusso acido. Il consumo di cibo alcalino o di una base, come un antiacido, neutralizza l'eccesso di acido, alleviando la sensazione di bruciore.

Questo è un esempio di una reazione acido-base. Gli acidi più semplici sono sostanze che contengono atomi di idrogeno dissociabili. In soluzioni acquose, rilasciano ioni idrogeno carichi positivamente, o protoni, insieme agli anioni corrispondenti.

I protoni reagiscono con le molecole d'acqua per formare ioni idronio. Per esempio, una soluzione acquosa di acido nitrico contiene ioni idronio e ioni nitrato. Altri acidi comunemente noti sono l'acido cloridrico, l'acido solforico e l'acido fosforico.

Gli acidi sono monoprotici o poliprotici a seconda del numero di atomi di idrogeno dissociabili per molecola. L'acido cloridrico e l'acido nitrico, con un idrogeno dissociabile ciascuno, sono entrambi esempi di acidi monoprotici, mentre l'acido solforico e l'acido fosforico sono poliprotici. L'acido solforico è diprotico e rilascia i suoi due protoni in sequenza, mentre l'acido fosforico è triprotico e si dissocia sequenzialmente in tre fasi.

Le basi più semplici sono composti che producono ioni idrossido carichi negativamente in soluzioni acquose. Basi facilmente identificabili contengono gruppi idrossilici;per esempio, idrossido di sodio, idrossido di potassio e idrossido di calcio. Tali basi, quando aggiunte all'acqua, si dissociano in ioni idrossido e nei corrispondenti cationi metallici.

Le basi non idrossido, come l'ammoniaca, reagiscono con l'acqua, accettando protoni dalle molecole d'acqua per produrre ioni ammonio e ioni idrossido. In generale, un acido e una base reagiscono per formare acqua e sale. Le reazioni acido-base sono anche dette reazioni di neutralizzazione quando le moli di protoni fornite dall'acido e le moli di ioni idrossido fornite dalla base sono uguali.

Per esempio, quando vengono miscelate quantità uguali di acido nitrico acquoso e idrossido di potassio acquoso, anche le quantità di ioni idronio e idrossido forniti alla soluzione sono uguali. Gli ioni idronio e idrossido, dunque, si neutralizzano completamente l'un l'altro combinandosi per formare acqua, senza lasciare dietro di sé ioni di idronio o idrossido. Inoltre, gli anioni nitrato e i cationi di potassio si uniscono per formare un sale:il nitrato di potassio.

Alcune reazioni di neutralizzazione sono reazioni di evoluzione del gas. Per esempio, l'acido cloridrico e il solfito di potassio reagiscono per formare cloruro di potassio, acqua e anidride solforosa, attraverso il sistema di equilibrio solfito-bisolfito.

acidi, basi e reazioni di neutralizzazione

Una reazione acido-base è quella in cui uno ione idrogeno, H^+, viene trasferito da una specie chimica a un'altra. Tali reazioni sono di fondamentale importanza per numerosi processi naturali e tecnologici, che vanno dalle trasformazioni chimiche allâ&#128;&#153;interno delle cellule o dei laghi e degli oceani alla produzione su scala industriale di fertilizzanti, prodotti farmaceutici e altre sostanze essenziali per la società.

Esistono diversi modi per definire un acido. Nel contesto delle soluzioni acquose, un acido è una sostanza che si dissolve per produrre ioni idrogeno.

<img alt="Eq1" src="https://www.jove.com/files/core/CDNSource/lessons/1029/1029_Equations-01.png" style="height: 40px;" />

Questa è la definizione di acido di Arrhenius, dal nome del chimico svedese Svante Arrhenius (1859-1927). Uno ione idrogeno, rappresentato dal simbolo H^+, è chiamato protone. In soluzione, i protoni si combinano chimicamente con le molecole d'acqua, attraverso le coppie solitarie dell'ossigeno, per formare ioni idronio, H_3O^+.

<img alt="Eq2" src="https://www.jove.com/files/core/CDNSource/lessons/1029/1029_Equations-02.png" style="height: 40px;" />

L'equazione chimica per la ionizzazione di un acido è scritta come

<img alt="Eq3" src="https://www.jove.com/files/core/CDNSource/lessons/1029/1029_Equations-03.png" style="height: 40px;" />

Gli acidi che reagiscono completamente con l'acqua in questo modo sono chiamati acidi forti. HCl, HNO_3 e HBr sono alcuni esempi.

La maggior parte degli acidi incontrati nella vita quotidiana sono acidi deboli. L'acido citrico nella frutta, l'acido acetico nell'aceto e l'acido lattico nel latte sono alcuni esempi. Un esempio familiare di acido debole è l'acido acetico, l'ingrediente principale dell'aceto alimentare. Quando disciolto in acqua in condizioni tipiche, solo circa l'1% delle molecole di acido acetico sono presenti nella forma ionizzata, CH_3CO_2^−.

<img alt="Eq4" src="https://www.jove.com/files/core/CDNSource/lessons/1029/1029_Equations-04.png" style="height: 40px;" />

L'uso di una doppia freccia nell'equazione di cui sopra denota l'aspetto di reazione parziale di questo processo.

Una base è una sostanza che si dissolve in acqua per produrre ioni idrossido, OH^−. Le basi più comuni sono composti ionici composti da cationi di metalli alcalini o alcalino terrosi (gruppi 1 e 2) combinati con lo ione idrossido, ad esempio NaOH e Ca(OH)_2. A differenza dei composti acidi discussi in precedenza, questi composti non reagiscono chimicamente con l'acqua; invece, si dissolvono e si dissociano, rilasciando ioni idrossido direttamente nella soluzione. Ad esempio, KOH e Ba(OH)_2 si dissolvono in acqua e si dissociano completamente per produrre cationi (rispettivamente K^+ e Ba^2+) e ioni idrossido, OH^−. Queste basi, insieme ad altri idrossidi che si dissociano completamente in acqua, sono considerate basi forti.

Consideriamo come esempio la dissoluzione dell'idrossido di sodio in acqua:

<img alt="Eq5" src="https://www.jove.com/files/core/CDNSource/lessons/1029/1029_Equations-05.png" style="height: 40px;" />

Quest&#146;equazione conferma che l'idrossido di sodio è una base. Quando disciolto in acqua, NaOH si dissocia per produrre ioni Na^+ e OH^−. Questo vale anche per qualsiasi altro composto ionico contenente ioni idrossido. Poiché il processo di dissociazione è essenzialmente completo quando i composti ionici si dissolvono in acqua in condizioni tipiche, NaOH e altri idrossidi ionici sono tutti classificati come basi forti.

A differenza degli idrossidi ionici, alcuni composti producono ioni idrossido quando disciolti reagendo chimicamente con le molecole d'acqua. In tutti i casi questi composti reagiscono solo parzialmente e quindi sono classificati come basi deboli. Questi tipi di composti sono abbondanti anche in natura e sono prodotti importanti in varie tecnologie. Ad esempio, la produzione globale della base debole ammoniaca è in genere ben superiore alle 100 tonnellate allâ&#128;&#153;anno perché è ampiamente utilizzata come fertilizzante agricolo, materia prima per la sintesi chimica di altri composti e ingrediente attivo nei detergenti domestici. Quando disciolta in acqua, l'ammoniaca reagisce parzialmente per produrre ioni idrossido, come mostrato qui:

<img alt="Eq6" src="https://www.jove.com/files/core/CDNSource/lessons/1029/1029_Equations-06.png" style="height: 40px;" />

Questa è, per definizione, una reazione acido-base che comporta il trasferimento di ioni H^+ dalle molecole d'acqua alle molecole di ammoniaca. In condizioni tipiche, solo circa lâ&#128;&#153;1% dellâ&#128;&#153;ammoniaca disciolta è presente come ioni NH_4^+.

Una reazione di neutralizzazione è un tipo specifico di reazione acido-base in cui i reagenti sono un acido e una base (ma non acqua) e i prodotti sono spesso sale e acqua:

<img alt="Eq7" src="https://www.jove.com/files/core/CDNSource/lessons/1029/1029_Equations-07.png" style="height: 40px;" />

Per illustrare una reazione di neutralizzazione, si consideri cosa succede quando un tipico antiacido come il latte di magnesia (una sospensione acquosa di Mg(OH)_2) solido) viene ingerito per alleviare i sintomi associati all'eccesso di acido nello stomaco (HCl):

<img alt="Eq8" src="https://www.jove.com/files/core/CDNSource/lessons/1029/1029_Equations-08.png" style="height: 40px;" />

Si noti che, oltre all'acqua, questa reazione produce un sale, il cloruro di magnesio. L'H^+ (aq) dell'acido (forte o debole) si combina con l'OH^− (aq) della base (o prodotto dalla reazione di una base debole con l'acqua) per formare H_2O (l). Ad esempio, la reazione tra soluzioni acquose di HCl (acido forte) e NaOH (base forte) è scritta come segue:

<img alt="Eq9" src="https://www.jove.com/files/core/CDNSource/lessons/1029/1029_Equations-09.png" style="height: 40px;" />

Sia HCl che NaOH subiscono una ionizzazione al 100%. Lâ&#128;&#153;equazione ionica completa, quindi, può essere scritta come:

<img alt="Eq10" src="https://www.jove.com/files/core/CDNSource/lessons/1029/1029_Equations-10.png" style="height: 40px;" />

Cl^- e Na^+ sono chiamati ioni spettatori, che si annullano, dando l'equazione ionica netta come:

<img alt="Eq11" src="https://www.jove.com/files/core/CDNSource/lessons/1029/1029_Equations-11.png" style="height: 40px;" />

Questo testo è adattato da <a href="https://openstax.org/books/chemistry-2e/pages/4-2-classifying-chemical-reactions">OpenStax Chemistry 2e, Section: 4.2: Classifying Chemical Reactions.</a>

Acidi, basi e reazioni di neutralizzazione

Una reazione acido-base è quella in cui uno ione idrogeno, H+, viene trasferito da una specie chimica all'altra. Tali reazioni sono di importanza centrale per...

Education

Didattica

Book

Chemistry

Chimica

Chemical Quantities and Aqueous Reactions

Quantità chimiche e reazioni in soluzione acquosa

chemical-quantities-and-aqueous-reactions

how acids and bases form ions

Acids and bases form ions in water through acid-base reactions. These reactions move a hydrogen ion, H+, from one chemical species to another. They matter in many natural and technological processes, from chemistry inside cells and in lakes and oceans to the large-scale production of fertilizers, pharmaceuticals, and other useful substances.

In water, an acid is a substance that produces hydrogen ions. This is the Arrhenius definition of an acid. The H+ ion is also called a proton. In solution, these protons combine with water molecules to form hydronium ions, H3O+.

Acids that react completely with water are called strong acids. Common examples include HCl, HNO3, and HBr. Most acids people encounter in daily life are weak acids. Citric acid in fruits, acetic acid in vinegar, and lactic acid in milk are examples. Acetic acid is a familiar weak acid, and under typical conditions only about 1% of its molecules are in the ionized form, CH3CO2−. A double arrow shows that this reaction is only partial.

A base is a substance that dissolves in water to yield hydroxide ions, OH−. The most common bases are ionic compounds made of alkali or alkaline earth metal cations from groups 1 and 2 with hydroxide ions, such as NaOH and Ca(OH)2. These compounds do not react chemically with water. Instead, they dissolve and dissociate, releasing hydroxide ions directly into solution.

KOH and Ba(OH)2 are examples of strong bases because they dissociate completely in water. The same is true for sodium hydroxide. When NaOH dissolves, it gives Na+ and OH− ions. Any ionic compound that contains hydroxide ions behaves this way under typical conditions, so these hydroxides are classified as strong bases.

Some compounds make hydroxide ions by reacting with water molecules instead of simply dissociating. These compounds react only partially, so they are weak bases. Ammonia is a common example. It is produced on a very large scale because it is used as an agricultural fertilizer, a starting material for chemical synthesis, and an ingredient in household cleaners. When ammonia dissolves in water, it reacts partially to form OH− and NH4+ ions. This is an acid-base reaction because H+ ions move from water molecules to ammonia molecules. Under typical conditions, only about 1% of dissolved ammonia is present as NH4+.

A neutralization reaction is a special acid-base reaction in which an acid and a base react, but water is not a reactant. The products are often a salt and water. Milk of magnesia is a common antacid made of solid Mg(OH)2 in water. It helps relieve excess stomach acid, HCl, by neutralizing it. This reaction forms water and the salt magnesium chloride.

In neutralization, H+(aq) from the acid combines with OH−(aq) from the base to make H2O(l). For example, HCl and NaOH are both completely ionized in water. Their complete ionic equation includes Na+ and Cl− ions, but these are spectator ions because they cancel out. The net ionic equation shows the essential change: H+(aq) + OH−(aq) → H2O(l).

How Acids and Bases Form Ions

precipitation reactions

Predicting Precipitation in Aqueous Reactions

Precipitation reactions happen when two aqueous solutions of soluble salts are mixed and an insoluble ionic compound forms. That solid is called a precipitate. The ions in solution exchange partners, so these reactions are also called double displacement, double replacement, exchange, or metathesis reactions. These reactions are useful in chemistry for identifying metal ions in a compound. They also support gravimetric methods, which measure composition by the mass of a substance. Whether a...

reaction stoichiometry

Using Balanced Equations to Predict Amounts

Balanced chemical equations show how much of each substance reacts and forms in a chemical change. The formulas identify the reactants and products, which helps classify the reaction. The coefficients show the relative numbers of each substance, which lets chemists measure the relationships between amounts consumed and produced. These quantitative relationships are called stoichiometry. The word comes from the Greek words stoicheion, meaning element, and metron, meaning measure. Stoichiometry...

acids, bases and neutralization reactions

Acids and bases form ions in water through acid-base reactions. These reactions move a hydrogen ion, H+, from one chemical species to another. They matter in many natural and technological processes, from chemistry inside cells and in lakes and oceans to the large-scale production of fertilizers, pharmaceuticals, and other useful substances. In water, an acid is a substance that produces hydrogen ions. This is the Arrhenius definition of an acid. The H+ ion is also called a proton. In...

limiting reactant

Limiting Reactant in Water Formation

Limiting reactants control how much product forms in a chemical reaction. In a balanced equation, the listed amounts of reactants and products are called stoichiometric amounts. In real reactions, the reactants are not always present in those exact proportions. The limiting reactant is the reactant that gets used up first. Once it is gone, the reaction stops making more product. The other reactant is called the excess reactant. Chemists often use extra amounts of one reactant to make sure the...

reaction yield

Calculating Percent Yield in Reactions

Percent yield shows how much product a chemical reaction actually makes compared with how much it should make. The expected amount is called the theoretical yield. It comes from the balanced chemical equation and the stoichiometry, or mole ratios, in that equation. The theoretical yield assumes that the limiting reactant is completely converted into the desired product. The product collected after a reaction is the actual yield. In many cases, the actual yield is lower than the theoretical...

general properties of solutions

Solvents, Solutes, and Solution Types

Solutions are common mixtures found in everyday life. Ocean water, air, and gasoline are all examples of solutions. These mixtures contain two or more types of atoms or molecules in varying amounts. A solution is a homogeneous mixture, which means its composition is uniform throughout. This is different from a heterogeneous mixture, which has a non-uniform composition. In a homogeneous mixture, the components are evenly spread out and thoroughly mixed. Every solution has a solvent and a...

solution concentration and dilution

Molarity and Dilution in Solutions

Molarity and dilution are key ideas for describing solution concentration. Concentration means the relative amount of one component in a solution. In many solutions, one component is present in much larger amount. That component is the solvent, which acts as the medium that holds the other parts dissolved or dispersed. Water is a very common solvent, so aqueous solutions are common on Earth. A solute is the component present at a much lower concentration than the solvent. Chemists often...

electrolyte and nonelectrolyte solutions

Conductivity in Electrolyte Solutions

Electrolyte solutions conduct electricity because they contain mobile ions. The amount of current depends on how many ions are present in the aqueous solution. A solution with more dissolved ions conducts better, while a solution with few or no ions conducts poorly. Strong electrolytes dissociate completely in water. This complete dissociation is shown with a single forward arrow. Water-soluble ionic compounds such as sodium chloride split into sodium cations and chloride anions in solution.

solubility of ionic compounds

Solubility Rules for Ionic Salts

Solubility rules help predict whether ionic salts will dissolve in water. Solubility is the maximum amount of solute that can dissolve in a given amount of solvent at a set temperature and pressure. It is often measured in molarity, or moles per liter (mol/L). A compound is soluble if it dissolves in water. When a soluble salt dissolves, its ions separate and spread evenly through the solution. This physical change is called dissociation. Potassium chloride, KCl, is a simple example. Water...

chemical reactions in aqueous solutions

Aqueous Reactions and Ionic Equations

Aqueous reactions are chemical reactions that take place in water. Water is a good solvent, so it can dissolve many substances. Because of that, many chemical reactions happen in aqueous solution. In high school chemistry, these reactions are often grouped into three common patterns: precipitation, acid-base, and oxidation-reduction. A precipitation reaction happens when ions in two aqueous ionic compounds exchange partners and form an insoluble salt, called a precipitate. In an acid-base...

oxidation–reduction reactions

Redox Reactions and Oxidation Numbers

Redox reactions are chemical changes in which electrons move between reactants, and oxidation numbers help track that change. The term oxidation once referred only to reactions with molecular oxygen, but it now covers a wider reaction class called oxidation-reduction, or redox, reactions. Some redox reactions form ionic products. A simple example is the reaction between sodium and chlorine that produces sodium chloride. To follow what happens to each reactant, chemists often write...

oxidation numbers

Assigning Oxidation States in Redox Reactions

Oxidation states help track electron transfer in redox reactions. An oxidation number, also called an oxidation state, is a hypothetical number that shows the effective charge of an atom or element. Chemists assign it by using a set of rules. In an ionic compound, oxidation numbers are based on how many electrons move between reacting species. For example, when calcium chloride forms, calcium loses two valence electrons and the two chlorine atoms each gain one electron. In CaCl2, calcium has...

acids, bases, and neutralization reactions

synthesis and decomposition reactions

Building and Breaking in Chemical Reactions

Synthesis and decomposition are two redox reactions that show how substances can be built up or broken down. Synthesis means to make something, while decomposition means to break something apart. These reactions also involve chemical changes and energy changes. Synthesis reactions are also called combination reactions. In a synthesis reaction, two or more substances join to form one more complex substance. They are often written as A + B → AB or A + B → C. One example is the formation of...

scientists in action

Scienziati all'opera

key terms

Termini chiave

key relationships & equations

Relazioni e Equazioni Chiave

chapter exercises

Esercizi del capitolo

appendices

Appendici

chemical quantities and aqueous reactions

Learn how acids and bases form ions in water, including strong and weak acids, strong and weak bases, ammonia, and neutralization reactions.

How Acids and Bases Form Ions | JoVE K12

chemistry

PS.PSc.2.6

Texas Essential Knowledge and Skills

High School

Chemistry and Physics

IPC.8

IPC.8.A

Pennsylvania State Academic Standards

Chemical Reactions

3.2.9-12.C

3.2.9-12.G

Louisiana Student Standards for Science

Matter And Its Interactions

HS-PS1-2

HS-PS1-7

ohios-learning-standards-and-model-curriculum

Ohio’s Learning Standards and Model Curriculum

Interactions Of Matter

Chemical reactions

Tennessee Academic Standards

Matter and Its Interactions

CHEM1.PS1.4

Arizona Science Standards

HS+C.P1

HS+C.P1U1.5

CHEM.9

CHEM.9.B

Alabama Course of Study Science

9-12.PS.3.5.d

9-12.PS.3.6.d

Florida Department of Education

SC.912.P.8

SC.912.P.8.8

new-york-state-science-learning-standards

New York State Science Learning Standards

HS. Chemical Reactions

HS-PS1-4.

HS-PS1-12.

Georgia Standards of Excellence

SC6.

Neutralization Reactions

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 ...

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 ...

Molecules and Compounds

Atoms and Molecules

Everything in the universe is made up of matter, and matter is composed of a combination of elements. An atom is the smallest unit of ...

Solution Formation

There is no one solvent that can dissolve every type of solute. Some substances that readily dissolve in a certain solvent might be insoluble in a ...

Colloids

Children at play often make suspensions such as mixtures of mud and water, flour and water, or a suspension of solid pigments in water known as tempera ...

Construct an explanation to classify matter as a pure substance or mixture; homogeneous or heterogeneous; element or compound; solution, colloid or suspension.

PS.PSc.1.1

Phase Transitions

Whether solid, liquid, or gas, a substance&#39;s state depends on the order and arrangement of its particles (atoms, molecules, or ions). Particles in the ...

phase-transitions-vaporization-and-condensation

Phase Transitions: Vaporization and Condensation

The physical form of a substance changes on changing its temperature. For example, raising the temperature of a liquid causes the liquid to vaporize ...

Vapor Pressure

When a liquid vaporizes in a closed container, gas molecules cannot escape. As these gas phase molecules move randomly about, they will occasionally ...

Clausius-Clapeyron Equation

The equilibrium between a liquid and its vapor depends on the temperature of the system; a rise in temperature causes a corresponding rise in the vapor ...

Phase Transitions: Melting and Freezing

Heating a crystalline solid increases the average energy of its atoms, molecules, or ions, and the solid gets hotter. At some point, the added energy ...

phase-transitions-sublimation-and-deposition

Phase Transitions: Sublimation and Deposition

Some solids can transition directly into the gaseous state, bypassing the liquid state, via a process known as sublimation. At room temperature and ...

Heating and Cooling Curves

When a substance&#8212;isolated from its environment&#8212;is subjected to heat changes, corresponding changes in temperature and phase of the substance ...

Phase Diagrams

A phase diagram combines plots of pressure versus temperature for the liquid-gas, solid-liquid, and solid-gas phase-transition equilibria of a substance. ...

Use models to compare the phases of matter and the physical changes they undergo.

PS.PSc.1.2

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 ...

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 ...

Intermolecular Forces

Atoms and molecules interact through bonds (or forces): intramolecular and intermolecular. The forces are electrostatic as they arise from interactions ...

comparing-intermolecular-forces-melting-point-boiling-point

Comparing Intermolecular Forces: Melting Point, Boiling Point, and Miscibility

Intermolecular forces are attractive forces that exist between molecules. They dictate several bulk properties, such as melting points, boiling points, ...

Carry out investigations to compare physical and chemical properties of matter.

PS.PSc.1.3

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 ...

The Bohr Model

Following the work of Ernest Rutherford and his colleagues in the early twentieth century, the picture of atoms consisting of tiny dense nuclei surrounded ...

Emission Spectra

When solids, liquids, or condensed gases are heated sufficiently, they radiate some of the excess energy as light. Photons produced in this manner have a ...

The de Broglie Wavelength

In the macroscopic world, objects that are large enough to be seen by the naked eye follow the rules of classical physics. A billiard ball moving on a ...

The Uncertainty Principle

Werner Heisenberg considered the limits of how accurately one can measure properties of an electron or other microscopic particles. He determined that ...

Use models to interpret the data presented in Bohr diagrams and electron dot diagrams for neutral atoms of elements 1 through 18.

PS.PSc.1.4

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 ...

Use models to compare representations of atoms, ions, and isotopes.

PS.PSc.1.5

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 ...

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 ...

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 the Periodic Table as a model to predict the relative properties (metallic/nonmetallic character, ionic charge, and reactivity) and arrangement of elements based on the pattern of valence electrons in the outermost energy levels of atoms.

PS.PSc.1.6

Understand types, properties, and structure of matter.

How Acids and Bases Form Ions

Description

Transcript

Tags

More videos by Standards