What did John Dalton NOT predict about the atom?
Atoms are tiny particles that make up elements
Atoms cannot be divided
Atoms have negative electrons which move around in a 'sea' of electrons
All atoms of a given element are the same
What is J J Thomson most famous for?
Working out the number of atoms in a mole
Discovering that cathode rays are made up of a stream of particles called electrons
Finding a law allowing people to indirectly determine the enthalpy change of a reaction
Shooting JFK
Who carried out the gold leaf experiment, in which alpha particles were fired at a thin sheet of gold foil?
Dalton
Hess
Rutherford
Bohr
Which of these are Rutherford's main conclusions from his experiment into the structure of the atom?
The positive charge and most of the mass of the atom are concentrated at the centre, in the nucleus Negative electrons orbit the nucleus Electrons follow only certain paths Most of the atom is made up of empty space
The atom is made up of negative electrons in a 'sea' of positive charge
Atoms cannot be divided Atoms are tiny particles that make up elements
The overall charge of an atom is 0 electrons orbit the nucleus Most of the atom is empty space The positive charge and most of the mass of an atom is centred in the middle, in the nucleus
what is the relative mass of an electron?
1
2000
1/2000
1/20 000
what is the definition of an isotope?
atoms of the same element with different numbers of neutrons
atoms of the same elements with different numbers of protons
atoms with different mass numbers
atoms with the same charges
How many atoms are in one mole?
6.02 x 10 to the power of 24
2.06 x 10 to the power of 13
6.02 x 10 to the power of 23
6.03 x 10 to the power of 24
what is the definition of relative isotopic mass?
the weighted mean mass of an atom compared to one-twelfth the mass of an atom of carbon-12
the weighted mean mass of an atom compared to twelve grams of carbon-12
the mass of an isotope of an element compared to twelve grams of carbon -12
the mass of an isotope of an element compare to one -twelfth the mass of one atom of carbon-12
what is the definition of relative atomic mass?
the weighted mean mass of an atom of an element compared to one-twelfth the mass of an atom of carbon-12
the weighted mean mass of an atom compared to 12 grams of carbon-12
the mass of an atom compared to one -twelfth the mass of an atom of carbon-12
the mass of an isotope of an element compared to one -twelfth the mass of one atom of carbon 12
what is the definition of a mole?
the amount of any substance containing as many particles as there are carbon atoms in exactly 12 grams of the crabon-12 isotope
the mass of 6.02 x 10 to the power of 23 atoms
a small mammal adapted to a subterranean lifestyle
the number of atoms per mole in a compound
how do you find the number of moles in a substance?
mr divided by the mass
mass divided by the mr
mass times the mr
mr squared minus the mass
what do you need to do to find the empirical formula?
list the elements, the mr, then divide by the smallest
list the elements, the experimental masses, number of moles, divide mass by moles, divide by smallest
list the elements, the experimental masses, mr, divide mass by mr, divide by smallest
list all the elements, experimental masses, mr, divide by smallest
what does Avogadro's hypothesis state?
there are 6.02 times 10 to the power of 23 molecules in a mole
the mr is calculated by adding the ar of all the elements present in the compound
the volume of gas stays the same regardless of RTP
equal volumes of gases at the same temperature and pressure contain equal numbers of molecules
what is the formula for calculating the number of moles present in a gas at RTP?
volume (dm cubed) divided by 24.0
volume (cm cubed) divided by 24.0
Volume (dm cubed) divided by 23.0
volume times mr divided by 24.0
what is the formula for calculating the number of moles in a liquid?
volume (cm cubed) times concentration
volume (dm cubed) divided by concentration
volume (dm cubed) times concentration
volume (dm cubed) times mr
What is the definition of an acid?
A substance with a pH of less than 7
A substance the neutralises an alkali
A proton donator
A dehydrated salt
What is the definition of an alkali?
A soluble base
A base that dissolves in water to release OH minus ions
A substance that is above pH 7
The opposite to an acid
What is the definition of a base?
A proton acceptor
A soluble alkali
A substance that is pH7
What is the formula of nitric acid?
NH2
HN03
H2NO3
NaCl
What is the definition of a salt?
Formed when an acid and an alkali neutralise each other
Formed when the H+ ion in an acid is replaced by a metal ion or other positive ion
A popular seasoning
A mildly acidic substance (pH5-6) that is formed in the presence of an acid catalyst
Acid + carbonate --> ??
Salt + hydrogen + water
Salt + hydrogen + carbon dioxide
Salt + hydrogen
Salt + carbon dioxide + water
Acid + base --> ??
Salt + water
Salt + oxygen + water
Acid + alkali --> ??
Salt + hydrogen + metal oxide
Metal oxide + hydrogen
What is the definition of... a) hydrated and b) anhydrous
a) a crystalline compound containing water molecules, b) and crystalline compound containing no water molecules
a) an aqueous solution, b) a liquid solution
a) a crystalline compound containing water molecules, b) a substance that contains no water molecules
a) a crystalline structure, b) a simple covalent structure
What does water of crystallisation refer to?
the water molecules that form an essential part of the crystalline structure of a substance
the water needed in order to hydrate a substance
water molecules that are able to form a crystalline structure under extreme conditions
the crystalline structure of non-metals
What is the oxidation number of an uncombined event?
0
-1
+2
What is the oxidation number of combined fluorine?
+1
+3
What is the oxidation number of combined oxygen?
-2
What is the oxidation number of combined hydrogen?
What is it called when electrons are lost from an element in a reaction?
Reduction
Reductation
Oxidation
Minimisim
What is it called when electrons are gained by an atom in a reaction?
Inheritance
Maximism
What is a reducing agent?
a reagent that oxidises another species
a reagent that is reduced in a reaction
a reagent that reduces another species
an atom that has been reduced
What is a redox reaction?
A reaction where the same element is both reduced and oxidised
A reaction which is both endo- and exothermic
A reaction that has a total enthalpy change of 0
A reaction in which both reduction and oxidation take place
What is an oxidising agent?
a species that has been oxidised
a reagent that accelerates the rate of reduction
a reagent that release energy when exposed to oxygen
