Chemistry Section 5 Chemical Bonding Chemistry 5.5: Metallic Bonds

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A covalent bond is one in which one or more pairs of valence electrons are shared by two atoms. Atoms share their valence electrons in a c__________ bond.

Atoms share their valence electrons in a c__________ bond. The permanent transfer of electrons between atoms creates an i_______ b______.

A third type of chemical bond is the metallic bond. A combination of metal atoms arranged in a lattice (grid) structure creates a m__________ b_______.

When a number of positively charged metal ions are joined by a strong electrostatic attraction, a m_______ b______ is formed.

This illustration shows a large number of positive silver (Ag) ions held together by a m_______ bond.

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When metallic bonds form, the valence electrons delocalize (a word that means the same as separate) from the outermost shell. Instead of orbiting their atoms, they form a "sea of electrons" surrounding the p_________ m_______ ions.

A common characteristic of metallic elements is they contain only one to three v_______ electrons in the outer shell.

The valence electrons leave individual atoms to become part of a common “sea of electrons” which hold the metal in a l_______ structure.

The valence electrons are loose because their parent atoms can't hold onto them, and are shared by all the metal ions in the l______ s________. The “sea of electrons” is also called the electron swarm. In a metallic bond valence electrons are called the e______ s_____.

Because the valence electrons are able to move around in the electron swarm, the floating nature of the e______ can conduct electricity.

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Because the valence electrons are able to move around in the electron swarm, the floating nature of the e______ can conduct heat or cold.

The existence of the e________ s_______ accounts for the good electrical and thermal conductivities of metals.

Electrons are influenced by a number of adjacent nuclei. The sharply defined levels of the atoms become bands of allowed energy, also known as the band theory. The range of energies that electrons can have in a solid are called the e______ b____. In any metal there are two distinct e_______ b______ in which electrons may exist, the valence band and conduction band.

There are two ranges of the energy bands, the valence band and the conduction band. The range of energies possessed by valence electrons is called v________ band.

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There are two ranges of the energy bands, the valence band and the conduction band. The range of energies possessed by free electrons is called the c__________ band.

The range of energies possessed by valence electrons is called v________ band.

The range of energies possessed by free electrons is called c__________ band.

The two ranges of the energy bands are the v________ band and the c________ band.

Electrons in the v________ b_______ are only weakly held to the nucleus of their atoms.

Electrons in the c________ b______ have escaped from their atoms to become free electrons, able to move much farther from the nucleus.

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Atoms share their valence electrons in a c__________ bond.

The permanent transfer of electrons between atoms creates an i_______ b______.

A combination of metal atoms arranged in a lattice (grid) structure creates a m__________ b_______.

Metals can be classified as conductors, insulators and semiconductors. A substance which allows electric current to pass through it is a c________.

A substance which prevents the flow of electricity is an i________.

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A metallic alloy which, when cooled to near absolute zero (273ºC), dramatically loses all electrical resistance is a s___________.

A metallic bond can be a c________, an i________, or a s__________.

A covalent bond is formed between atoms which share electrons. An ionic bond is formed between atoms of metal and nonmetal elements. A metallic bond is formed between m______ and alloys.

REVIEW

A combination of metal atoms arranged in a lattice (grid) structure creates a m__________ b_______.

Instead of orbiting their atoms, the valence electrons form a "sea of electrons" surrounding the p_________ m_______ ions.

In a metallic bond valence electrons are called the e______ s_____.

In any metal there are two distinct e_______ b______ in which electrons may exist, the valence band and conduction band.

The range of energies possessed by valence electrons is called v________ band. 6

The range of energies possessed by free electrons is called c__________ band.

A metallic bond can be a c________, an i________, or a s__________.

A combination of metal atoms arranged in a lattice (grid) structure creates a m__________ b_______.

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