A LEVEL EDEXCEL PAPER 3 GENERAL AND PRACTICAL PRINCIPLES IN CHEMISTRY

A LEVEL EDEXCEL PAPER 3 GENERAL
AND PRACTICAL PRINCIPLES IN
CHEMISTRY COMPREHENSIVE TEST PAPER
2026 FULL QUESTIONS AND CORRECT
ANSWERS GRADED A+

⩥Mass number. Answer: Protons plus neutrons


⩥Atomic number. Answer: Protons or electrons


⩥Isotopes. Answer: Atoms with identical atomic numbers, but different
mass numbers


⩥1 g =. Answer: 6.02214 X 10^23 amu


⩥Molecular mass. Answer: Sum of atomic masses of each atom in
molecule
Ex. NaCl


⩥Formula mass. Answer: Sum of atom masses of each atom in formula
unit
Ex. CaCl2

,⩥Atomic mass formula. Answer: (Isotope mass) (fractional isotope
abundance) + (Isotope mass) (fractional isotope abundance)


⩥Cathode ray. Answer: Streams of electrons produced when high
voltage is applied to electroloids in evacuated tube


⩥Radioactivity. Answer: Spontaneous emission of radiation


⩥Alpha radiation. Answer: Fast moving
2+ charge


⩥Beta radiation. Answer: High speed electrons
1- charge


⩥Three types of radiation Rutherford discovered. Answer: Alpha (a)
Beta (B)
Gamma (y)


⩥Periodic table periods. Answer: Rows


⩥Periodic table groups. Answer: Columns

, ⩥Diatomic molecules (define and list). Answer: Made up of two atoms
H, F, O, N, Cl, Br, I


⩥Molecular formula. Answer: Indicates actual numbers of atoms in a
molecule
Ex. H2O2


⩥Empirical formula. Answer: Indicates only relative number of atoms of
each type in a molecule
Ex. HO


⩥Ion. Answer: Charged particle formed when atoms gain or lose
electrons


⩥Naming ionic compounds (one type of ion). Answer: Metal +
nonmetal(ide)
Ex. CaCl2 = calcium chloride


⩥Naming ionic compounds (two or more different ions). Answer: Metal
(charge as roman numeral) + nonmetal(ide)
Ex. FeF3 = iron(III) fluoride