Key Words Flashcards
What is a group?
Vertical column in the periodic table. Elements in a group have similar properties
What is diffusion?
Movement of particles from a region of high concentration to a region of low concentration.
What is a period?
A period is a horizontal row in the periodic table.
What does property mean? e.g. What’s the property of a metal?
the property of something is what they all have as a group. (Characteristics of a substance) E.g. Metals are shiny, conduct electricity and hard.
What is an element?
An item with only one type of atom.
What is a compound?
A substance that is made of 2 or more different types of atoms joined together.
What is a mixture?
A mixture is a mixture of elements and/or compounds in any ratio. The properties of separate elements stay with them.
What is Thermal Decomposition?
The breaking down of a substance into simpler substances using heat.
e.g copper carbonate –> copper oxide + carbon dioxide.
What is limewater used for?
Test for Carbon Dioxide, if it’s present, it goes cloudy/milky.
What is Electrolysis?
The decomposition of a compound into simpler substances using electricity.
What is an Anode?
The positive electrode
What is a cathode?
The negative electrode
What is an electrolyte
The solution containing ions to be electrolysed
What is an ion?
A charged particle e.g. H+ or Cl-
What is an isotope?
An isotope is an element with the same number of protons BUT a different number of neutrons
Describe electron arrangement
The electrons are arranged in energy levels, ‘shells’. They can hold 2 or 8 electrons per shell, it goes in the formation 2,8,8,2
What is the Atomic mass?
Sum of neutrons and protons
What is the atomic number?
The number of protons
What is the nucleus?
The centre of the atom, it holds protons and neutrons
What is a proton?
A positively charged particle in the nucleus with a mass of ‘1’.
What is an electron?
A negatively charged particle found around the nucleus in shells.
What is a neutron?
A particle found in the nucleus with no charge and a mass of ‘1’. Can be calculated by subtracting the atomic number from the atomic mass.
What is combustion?
Combustion occurs when a substance reacts with oxygen releasing energy mainly in the form of light and heat.
- Combustion is an oxidation reaction
- the substance burnt gains oxygen and gets heavier
What is Corrosion?
The process which a metal reacts with oxygen in the air to form a solid on a surface.
What is rusting?
Corrosion of iron or steel
What is Rust?
Hydrated Iron Oxide
What is sacrificial protection?
Attaching a more reactive metal to iron or steel, which corrodes instead of that
What is galvanising?
Protecting the iron by dipping it in molten zinc. This is known as a double protection as it’s sacrificial protection and a physical barrier.
What is oxidation?
When a substance gains oxygen. e.g. Iron going rusty
What is reduction?
When a substance loses oxygen
