Atomic Structure
Atoms
What are all substances made from?
Ionic, covalent and metallic
Name the three types of chemical bond
No atoms are lost or made during a chemical reaction so the mass of the products equals the mass of the reactants
What is the law of conservation of mass?
Metals react with oxygen to produce metal oxides
What is produced when a metal reacts with oxygen?
Transfers energy to the surroundings so the temperature of the surroundings increases
What is an Exotherminc reaction?
The formation of one or more new substances, and often involve a detectable energy change
How would you know if a chemical reaction has happened?
The electrons are transferred
When a metal reacts with a non-metal during ionic bonding, what happens to the electron on the outer shell of the metal?
The relative formula mass (RFM) of a compound is the sum of the relative atomic masses of the atoms in the numbers shown in the formula
How do you calculate RFM?
It's tendency to form positive ions
What is the reactivity of a metal based on?
Self-heating can
What is one use of an exothermic reaction?
Tiny spheres that could not be divided
Before the electron was discovered, what did
people think atoms were?
Strong electrostatic forces of attraction between oppositely charged ions
Describe how ionic compounds are held together
6.02 x 10 23 particles per mole
What is Avagadro's Constant?
A salt and hydrogen
What is produced when a metal reacts with an
acid?
The activation energy
What is the minimum amount of energy required for a chemical reaction to start?
He suggested electrons orbit the nucleus at specific distances
How did Niels Bohr adapt the nuclear model of the atom?
Covalent bonding
When atoms share electrons, what type of
bonding is this?
Limiting reactant
What is the name of the reactant that gets
completely used up in reaction?
Soluble salts can be made from acids by reacting them with solid insoluble substances, such as metals, metal oxides, hydroxides or carbonates
How can you make a soluble salt?
The energy needed to break bonds and the energy released when bonds are formed can be calculated from bond energies
How can you calculate the energy needed to break bonds and releases from bonds?
What is the radius of an atom?
(about 1 x 10 -14 m)
It is these intermolecular forces that are overcome, not the covalent bonds, when the substance melts or boils
How can small covalent molecules melt and boil or easily when covalent bonding is strong?
g/dm3
What are the units of concentration in a
solution?
Partially Ionising
How ionising is a weak acid in aqueous solution?
The energy released from forming new bonds is greater than the energy needed to break existing bonds
Is the energy released in an exothermic reaction greater or less than the energy needed to break existing bonds?