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OCR A A-Level Chemistry- Physical and
inorganic (Paper 1) Questions & 100%
Correct Answers- Latest Test | Graded A+
| Passed
Isotopes
֎ -:- Atoms of the same elements with different numbers of neutrons and
different masses
Why do isotopes of the same element have the same chemical properties?
֎ -:- Same number of electrons, number of neutrons has no effect on reactions
of an element
Relative isotopic mass
֎ -:- Mass of an isotope relative to 1/12th of the mass of an atom of carbon-12
Relative atomic mass
֎ -:- The weighted mean mass of an atom of an element compared with 1/12th
of the mass of an atom of carbon-12.
Empirical formula
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֎ -:- The simplest whole number ratio of atoms of each elements in a
compound
Molecular formula
֎ -:- The number and type of atoms of each element in a molecule
Hydrated crystal
֎ -:- Water molecules part of its crystalline structure
Anhydrous crystal
֎ -:- Water molecules not part of its crystalline structure
Assumptions of water of crystallisation experimental formulae
֎ -:- All the water has been lost and no further decomposition
Standard solutioin
֎ -:- Solution of known concentration
Molar gas volume
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֎ -:- The volume per mole of gas molecules at a stated temperature and
pressure
Benefits of high atom economy
֎ -:- Makes industrial processes more efficient, preserves raw materials and
reduces waste
Strong acid
֎ -:- An acid that completely dissociates in solution
Weak acid
֎ -:- An acid that only partially dissociates in solution
Base
֎ -:- A substance that neutralises an acid to form a salt
Alkali
֎ -:- A base that dissolves in water forming OH- ions
Oxidation number of H in metal hydrides
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֎ -:- -1
Oxidation number of O in peroxides
֎ -:- -1
Oxidation number of O bonded to F
֎ -:- +2
Oxidation in terms of electrons
֎ -:- Loss of electrons
Oxidation in terms of oxidation number
֎ -:- increase in oxidation number
Reduction in terms of electrons
֎ -:- gain of electrons
Reduction in terms of oxidation number
֎ -:- decrease in oxidation number
26/08/2024 | © Copyright- This work may not be copied for profit.
OCR A A-Level Chemistry- Physical and
inorganic (Paper 1) Questions & 100%
Correct Answers- Latest Test | Graded A+
| Passed
Isotopes
֎ -:- Atoms of the same elements with different numbers of neutrons and
different masses
Why do isotopes of the same element have the same chemical properties?
֎ -:- Same number of electrons, number of neutrons has no effect on reactions
of an element
Relative isotopic mass
֎ -:- Mass of an isotope relative to 1/12th of the mass of an atom of carbon-12
Relative atomic mass
֎ -:- The weighted mean mass of an atom of an element compared with 1/12th
of the mass of an atom of carbon-12.
Empirical formula
26/08/2024 | © Copyright- This work may not be copied for profit.
, Excellence is key | 2024/2025 ~Page |2
֎ -:- The simplest whole number ratio of atoms of each elements in a
compound
Molecular formula
֎ -:- The number and type of atoms of each element in a molecule
Hydrated crystal
֎ -:- Water molecules part of its crystalline structure
Anhydrous crystal
֎ -:- Water molecules not part of its crystalline structure
Assumptions of water of crystallisation experimental formulae
֎ -:- All the water has been lost and no further decomposition
Standard solutioin
֎ -:- Solution of known concentration
Molar gas volume
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֎ -:- The volume per mole of gas molecules at a stated temperature and
pressure
Benefits of high atom economy
֎ -:- Makes industrial processes more efficient, preserves raw materials and
reduces waste
Strong acid
֎ -:- An acid that completely dissociates in solution
Weak acid
֎ -:- An acid that only partially dissociates in solution
Base
֎ -:- A substance that neutralises an acid to form a salt
Alkali
֎ -:- A base that dissolves in water forming OH- ions
Oxidation number of H in metal hydrides
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֎ -:- -1
Oxidation number of O in peroxides
֎ -:- -1
Oxidation number of O bonded to F
֎ -:- +2
Oxidation in terms of electrons
֎ -:- Loss of electrons
Oxidation in terms of oxidation number
֎ -:- increase in oxidation number
Reduction in terms of electrons
֎ -:- gain of electrons
Reduction in terms of oxidation number
֎ -:- decrease in oxidation number
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