Chemistry Flashcards
(25 cards)
Describe the Organisation of the Periodic Table
The chemical elements are arranged in order of increasing atomic number. The horizontal rows are called ‘periods’ and the vertical columns are called ‘groups’.
Explain the bonding behaviour of noble/inert gases
Noble/Inert gases do not form any chemical bonds due to having a complete electronic doublet.
Define ‘Ions’
‘Ions’ are atoms that are charged through the loss or gain of electrons.
Define ‘Cations’
‘Cations’ are positively charged ions created through the loss of electrons. (Usually metals).
Define ‘Anions’
‘Anions’ are negatively charged ions through the gain of electrons. (Usually non-metals).
How are ‘Ionic Compounds’ formed?
‘Ionic Compounds’ are formed through the atoms coming in contact with one another and lose or gain electrons.
What is the ‘force of attraction’ between ions called? What is the purpose?
‘Ionic Bonding’ is for atoms to achieve a fuller valence shell and increase its stability.
Properties/Characteristics of Ionic Compounds (4).
- Ions are arranged in a tight lattice structure.
- Usually solids within room temperature.
- High melting points due to the very strong electrostatic force of attraction.
- Dissolves in water forming aqueous solutions.
How are ‘Covalent Compounds’ formed?
‘Covalent Compounds’ are formed through two or more atoms coming in contact with one another and share electrons. (Occurs between two non-metals).
What is a ‘Covalent Bond’? What is the purpose?
‘Covalent Bond’ are shared electrons between two or more atoms. The purpose is to achieve a fuller valence shell and increase its stability.
Why do atoms have no overall charge?
Atoms have no overall charge due to having an equal amount of negative and positive charges, cancelling each other out.
Acid + Base = ?
Acid + Base = Salt + Water
Acid + Metal = ?
Acid + Metal = Salt + Hydrogen
Acid + Carbonate = ?
Acid + Carbonate = Salt + Water + Carbon Dioxide
What are ‘Combustion’ Reactions? What are the 2 types?
When a substance reacts with oxygen and heat is released.
1. Fuel + Oxygen = Carbon Dioxide + Water
2. Metal + Oxygen = Metal Oxide
What are ‘De-combustion’ Reactions?
One compounds breaks down into to simpler elements.
e.g. Water = Hydrogen + Oxygen
What are ‘Precipitation’ Reactions?
When two aqueous solutions are mixed, ions start to form two new compounds and a solid substance.
e.g. barium chloride + sodium sulfate = sodium chloride + barium sulfate.
What are ‘Displacement’ Reactions? What are the 2 types?
Using the reactivity series of metals.
1. Single Displacement
e.g. copper + silver nitrate = copper nitrate + silver.
2. Double Displacement
e.g. hydrogen iodide + zinc nitrate = hydrogen nitrate = zinc iodide.
What are ‘Synthesis’ Reactions?
The building up of compounds by simpler substances.
A + B = AB
e.g. sodium + chlorine = sodium chloride
e.g. hydrogen + oxygen = water.
What is the application of the ‘Law of Conservation of Matter’
Mass can neither be created or destroyed.
What are the 4 ways to speed up the rate of reactions?
- Increasing Concentration
- Increasing Temperature
- Increasing Surface Area
- Adding a Catalyst
What does increasing concentration do to speed up the rate of reactions?
The increase in concentration leads to increased collisions resulting in a faster reaction rate.
e.g. fanning a campfire to speed up burning the wood.
How does increasing temperature speed up the rate of reactions?
The increase in temperature leads to an increase in kinetic energy and particles start colliding frequently resulting in reactants turning into products faster.
e.g. increasing the heat on the stove to cook the food faster.
How does the increase in surface area speed up the rate of reactions?
A finely divided solid has more surface area than one large piece of the substance, reactants come in contact with other reactants frequently and reactants turn into products faster.
