2.3 Types of substances and conductivity

• Scheikunde
• Middelbare school
• vwo
• Leerjaar 3

2.4 types of substances and conductivity

Molecules

A molecule is the smallest particle of a substance with the same properties of that substance.

• The molecule model shows what a molecule looks like
• A few nanometers (1nm= 0.000000001mm)

The molecule model of water

Molecules in different fases

Types of substances

Different atoms

types of substances

• Metals  
• Molecular substances
• Salts

Metals

A substance consisting only of metal atoms

Shiny surface

formable

conduct heat

Conduct electricity in solid and liquid phase

Corrosion sensitivity

A process in which a metal reacts with oxygen and water. 

• With iron it's called rusting.
• Some types of metals are more sensitive for corrosion than others

Precious metals

Metals that do not react with oxygen and water

Gold

Silver

Platinum

semi-precious metals

Metals that react with difficulty with oxygen and water

Mercury

Copper

Base metals

metals that react with water and oxygen

Iron

Zinc

Very base metals

Metals that react very violently with oxygen and water

Potassium

Sodium

Magnesium

Alloy

Two or more types of metal atoms combined is called an alloy.

Used to make a metal stronger 

In which fase can metals conduct electricity?

1. Gas and liquid
2. dissolved and gas
3. liquid and dissolved
4. solid and liquid

What are base metals?

1. Metals that do not react with oxygen and water
2. Metals that react with difficulty with oxygen and water
3. Metals that react easily with water and oxygen
4. Metals that react very violently with oxygen and water

Molecular substances

Connections between non-metal atoms

 Few common features

do not conduct electricity

Molecules

Salts

Decomposable substances consisting of metal atoms and non-metal atoms.

Strong but fragile

Do not conduct electricity as a solid

In liquid or dissolved phase, salts can conduct electricity because the particles then move freely

Which types of atoms is a molecular substance made of?

1. non-metalatoms
2. metalatoms
3. non-metalatoms and metalatoms

In which phase can a salt conduct electricity?

1. Solid and liquid
2. gas and solid
3. dissolved and gas
4. dissolved and liquid