2) Properties of Solids

Melting

Solid system absorbs energy and weakens attractive forces between particles and changes to liquid state

Solid system absorbs energy and weakens attractive forces between particles and changes to liquid state

melting

What happens when molecules melt?

IMFs weaken

In what do IMFs weaken when melted?

molecules

What happens when ionic compounds are melted?

ionic bonds (lattice energy) weakens

In what do ionic bonds (lattice energy) weaken when melted?

ionic compounds

What is melting point?

Temperature (measure of energy) at which a substance undergoes melting

What describes the temperature (measure of energy) at which a substance undergoes melting?

melting point

What do stronger attractive forces between particles mean?

higher melting point (more energy required)

What means higher melting point (more energy required)

stronger attractive forces between particles

Molecular solids are compounds with what?

strong covalent forces between atoms and weak IMFs between molecules

What has strong covalent forces between atoms and weak IMFs between molecules?

molecular solid compounds

IMFs must weaken for what to melt?

molecular solids

What must happen for molecular solids to melt?

IMFs must weaken

What are examples of molecular solids?

sugar crystrals

What are sugar crystals an example of?

molecular solids

What are some characteristics of molecular solids?

relatively soft, have low melting points, and don’t conduct electricity when dissolved in water or as a solid

What are relatively soft, have low melting points, and don’t conduct electricity when dissolved in water or as a solid?

molecular solids

What are covalent network solids?

atoms that are covalently bonded in large networks or chains

What are atoms that are covalently bonded in large networks or chains?

covalent network solids

What are some characteristics of covalent network solids?

very hard, have high melting points, and covalent bonds must weaken to melt solid

What are very hard, have high melting points, and covalent bonds must weaken to melt solid?

covalent network solids

What are the four common covalent network solids?

C Diamond and Graphite, Si, and SiO2

C Diamond and Graphite, Si, and SiO2 are the what?

four common covalent network solids

Diamond C

all carbons are connected by covalent bonds and are one of the strongest materials

Which covalent network solid have all carbons connected by covalent bonds, and are one of the strongest materials

Diamond C

Graphite C

Sheets of covalent networks of carbon are weakly bonded to another sheet

In what covalent network solid are sheets of covalent networks weakly bonded to another sheet?

Graphite C

What are some examples of Covalent Network Solid SiO2?

quartz, sand, and glass

Quartz, sand, and glass are examples of which covalent network solid?

SiO2

What happens in ionic solids?

ionic bonds connect positive and negative ions to form crystal lattice structures

In what do ionic bonds connect positive and negative ions to form crystal lattice structures?

ionic solids

What are the characteristics of ionic solids?

Hard and brittle, have a high melting point, and are a poor conductor of heat and electricity as a solid

What are hard brittle, have a high melting point, and are a poor conductor of heat and electricity as a solid?

ionic solids

What happens when ionic compounds are melted or dissolved in water?

they can conduct an electric current because their ions are free to move and can carry electric current

What can conduct an electric current because their ions are free to move and can carry electric current?

ionic compounds when melted or dissolved in water

What happens in metallic solids?

they form crystalline structures and are a sea of electrons

What forms crystalline structures and are a sea of electrons?

metallic solids

What are the characteristics of metallic solids?

excellent conductors of heat and electricity, malleable, ductile, and have varying hardness and melting points

What are excellent conductors of heat and electricity, malleable, ductile, and have varying hardness and melting points?

metallic solids

What are the solids that can conduct electricity?

metals

Metals are the only solids that can do what?

conduct electricity