METALLIC BONDING [dchemlc]

what is metallic bonding?

• the electrostatic forces of attraction between each positive ion and the delocalised electrons.

• the electrostatic forces of attraction between the nuclei of the atoms that make up the bond, and the shared pair of electrons

• the electrostatic forces of attraction between positive and negative ions

• the electrostatic forces of attraction between the nucleus of an atom and its electrons

Answer explanation

Metallic bonding is the electrostatic forces of attraction between each positive ion and the delocalized electrons. This holds the structure together.

Tags

NGSS.HS-PS1-3

what is the charge of the ions formed by group 2 metals?

• 2

• 1

• -2

• -1

Answer explanation

The ion formed by the metal depends on the number of electrons the original atom has in its outer shell. Thus all the elements in Group 1 form

1+ ions and all the elements in Group 2 form 2+ ions.

Tags

NGSS.HS-PS1-1

In metals, the electrostatic forces of attraction between the positive ions and the delocalised electrons are strong. What is the proof of this?

• metals have high melting points

• metals have low melting points

• metals react with acid to give hydrogen and a salt

• metals have delocalized electrons which are free to move

Answer explanation

Most metals are hard and have high melting points. This suggests that the electrostatic forces of attraction between the positive ions and the delocalised electrons are strong.

Tags

NGSS.HS-PS1-3

NGSS.HS-PS2-4

why are metals good conductors of electricity?

• because the delocalised electrons are free to move throughout the structure.

• because the positive ions are free to move throughout the structure.

• because they have high kinetic energy.

• because they can pass current from molecule to molecule.

Answer explanation

Metals conduct electricity because the delocalised electrons are free to move throughout the structure.

Tags

NGSS.HS-PS1-1

metals are malleable. What is the meaning of malleable?

• Metals can be hammered into different shapes

• Metals can be stretched into long wires

• Metals can react with water

• Metals release their valence electrons

Answer explanation

Metals can be hammered into different shapes; this is what the word malleable means.

metals are ductile. What is meant by the word ductile?

• Metals can be drawn out into wires

• Metals can be hammered into any shape

• Metals can react with water

• Metals release their valence electrons

Answer explanation

Metals can be described as ductile. This means that they can be drawn out into wires.

why are metals malleable and ductile?

• because the layers of positive ions can slide over each other.

• because the positive ions are free to move throughout the structure.

• because the delocalized electrons are free to move throughout the structure

• because they bend on heating

Answer explanation

Tags

NGSS.HS-PS1-3

which of the following metals have the stronger metallic bonds?

• Na

• Mg

• Ne

• N

Answer explanation

Magnesium has two outer electrons, both of which are delocalised into the 'sea', leaving behind ions that carry a charge of 2+. There is a much stronger electrostatic attraction between the 2+ ions and the delocalised electrons. This means that the bonding is stronger in magnesium and the melting point is higher compared to sodium which has 1+ ions and one electron left behind in the sea.

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-3

which of the following diagrams show the 2D structure of calcium metal?

• 
• 
• 
• 

Answer explanation

Make sure you know how to represent a metallic lattice by a 2D diagram.

Tags

NGSS.HS-PS1-3

what is a metallic structure?

• a lattice of positive ions in a sea of delocalised electrons

• a lattice of negative ions in a sea of delocalised electrons

• a lattice of positive ions in a sea of negative ions

• a lattice of positive electrons in a sea of delocalised ions

Answer explanation

A metallic structure consists of a lattice (regular arrangement) of positive ions in a sea of delocalised electrons.

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-3