A LEVEL CHEMISTRY OCR A
COMPREHENSIVE EXAMINATION TEST
QUESTIONS AND SOLUTIONS FULLY
VERIFIED
●● Neutron
Answer: No charge
Mass of 1
●● Electron
Answer: -1 Charge
Mass of 1/200th
●● atomic number
Answer: number of protons
●● Isotope
Answer: An atom with the same number of protons and a different
number of neutrons
●● Nucleon number
Answer: number of protons and neutrons in the nucleus
,●● Cation
Answer: positive ion
●● Anion
Answer: negative ion
●● Standard Mass
Answer: 1/12th of a Carbon atom
●● Relative Atomic Mass
Answer: The weighted mean mass of an atom of an element compared
with one-twelfth of the mass of an atom of carbon-12.
●● Mass Spectrometer
Answer: used to measure the masses and abundances of isotopes
1. Placed in the meter
2. Vaporised and ionised to cations
3. Accelerated forward and heavier ions get left behind
4. Gives a M/Z ratio
●● Avogadro's Constant
,Answer: Number of particles in a mole - 6.02 x 10^23
●● Empirical Formula
Answer: a formula with the lowest whole-number ratio of elements in a
compound
●● Molecular Formula
Answer: The number of atoms of each element in a molecule.
●● Standard Solution
Answer: Solution of known concentration
1. Weigh the solid
2. Dissolve with distilled water
3. Pour into a volumetric flask and rinse the beaker out
4. Fill until the bottom of the meniscus is at the point of the mark
5. Invert the flask several times to ensure an even mix
●● Percentage Yield
Answer: actual yield/theoretical yield x 100
●● Atom Economy
Answer: (Molecular mass of desired products/ Molecular mass of all
products) x 100
, ●● Strong acid
Answer: Completely dissociates in solution.
●● weak acid
Answer: Partly dissociates in solution
●● Base
Answer: Substance that neutralises acids to form a salt
●● Alkali
Answer: A base that is soluble in water to release OH- ions
●● Tetrahedral
Answer: 4 bonds, 109.5 degrees
●● Pyramidal
Answer: 3 bonds, 1 lone pair, 107 degrees
●● Non - linear
Answer: 2 bonds, 2 lone pairs, 104.5 degrees
COMPREHENSIVE EXAMINATION TEST
QUESTIONS AND SOLUTIONS FULLY
VERIFIED
●● Neutron
Answer: No charge
Mass of 1
●● Electron
Answer: -1 Charge
Mass of 1/200th
●● atomic number
Answer: number of protons
●● Isotope
Answer: An atom with the same number of protons and a different
number of neutrons
●● Nucleon number
Answer: number of protons and neutrons in the nucleus
,●● Cation
Answer: positive ion
●● Anion
Answer: negative ion
●● Standard Mass
Answer: 1/12th of a Carbon atom
●● Relative Atomic Mass
Answer: The weighted mean mass of an atom of an element compared
with one-twelfth of the mass of an atom of carbon-12.
●● Mass Spectrometer
Answer: used to measure the masses and abundances of isotopes
1. Placed in the meter
2. Vaporised and ionised to cations
3. Accelerated forward and heavier ions get left behind
4. Gives a M/Z ratio
●● Avogadro's Constant
,Answer: Number of particles in a mole - 6.02 x 10^23
●● Empirical Formula
Answer: a formula with the lowest whole-number ratio of elements in a
compound
●● Molecular Formula
Answer: The number of atoms of each element in a molecule.
●● Standard Solution
Answer: Solution of known concentration
1. Weigh the solid
2. Dissolve with distilled water
3. Pour into a volumetric flask and rinse the beaker out
4. Fill until the bottom of the meniscus is at the point of the mark
5. Invert the flask several times to ensure an even mix
●● Percentage Yield
Answer: actual yield/theoretical yield x 100
●● Atom Economy
Answer: (Molecular mass of desired products/ Molecular mass of all
products) x 100
, ●● Strong acid
Answer: Completely dissociates in solution.
●● weak acid
Answer: Partly dissociates in solution
●● Base
Answer: Substance that neutralises acids to form a salt
●● Alkali
Answer: A base that is soluble in water to release OH- ions
●● Tetrahedral
Answer: 4 bonds, 109.5 degrees
●● Pyramidal
Answer: 3 bonds, 1 lone pair, 107 degrees
●● Non - linear
Answer: 2 bonds, 2 lone pairs, 104.5 degrees
