Latest physical science AFOQT Key Exam Guide
Questions and Full Solution Version 2025/2026
Half-life - correct answer the time it takes for the radiation coming from a
sample of a radioactive element to decrease by half
Heat - correct answer the energy that is transferred when a substance is
at a different temperature to that of its surroundings
Heat capacity - correct answer the ratio of the heat supplied to a
substance, compared with the rise in temperature that is produced.
Heat of combustion - correct answer the amount of heat given off by a
mole of substance during combustion. This heat is a property of the
substance and is the same no matter what kind of combustion is involved.
Example: heat of combustion of carbon is 94.05 kcal (x4.18 kj/kcal=393.1
kj)
Ion - correct answer an atom, or group of atoms, that has gained or lost
one or more electrons and so developed an electrical charge. Ions behave
differently from electrically neutral atoms and molecules. They can move in
an electric field, and they can also bind strongly to solvent molecules such
as water. Positively charged ions are called cations; negatively charged
ions are called anions. Ions can carry an electrical current through
solutions.
Isotope - correct answer one of two or more atoms of the same element
that have the same number of protons in their nucleus (atomic number), but
which have a different number of neutrons (atomic mass). Example;
carbon-12 and carbon-14.
, Kinetic energy - correct answer the energy an object has by virtue of its
being in motion.
Latent heat - correct answer the amount of heat that is absorbed or
released during the process of changing state between gas, liquid or solid.
For example, heat is absorbed when a substance melts and it is released
again when the substance solidifies.
Liquid/liquid phase - correct answer a form of matter that has a fixed
volume but not fixed shape
Mass - correct answer the amount of matter in an object. In everyday use
the word weight is often used (somewhat incorrectly) to mean mass.
Matter - correct answer anything that has mass and takes up space.
Melting point - correct answer the temperature at which a substance
changes state from a solid phase to a liquid phase. It is the same as
freezing point.
Metal - correct answer a class of elements that is good conductor of
electricity and heat, has metallic luster, is malleable and ductile, forms
cations and has oxides that are bases. Metals are formed as cations held
together by a sea of electrons. A metal may also be an alloy of these
elements. Example sodium, calcium, gold.
Mixture - correct answer a material that can be separated into two or more
substances using physical means. Example: a mixture of copper (ii) sulfate
and cadmium sulfide can be separated by filtration.
Questions and Full Solution Version 2025/2026
Half-life - correct answer the time it takes for the radiation coming from a
sample of a radioactive element to decrease by half
Heat - correct answer the energy that is transferred when a substance is
at a different temperature to that of its surroundings
Heat capacity - correct answer the ratio of the heat supplied to a
substance, compared with the rise in temperature that is produced.
Heat of combustion - correct answer the amount of heat given off by a
mole of substance during combustion. This heat is a property of the
substance and is the same no matter what kind of combustion is involved.
Example: heat of combustion of carbon is 94.05 kcal (x4.18 kj/kcal=393.1
kj)
Ion - correct answer an atom, or group of atoms, that has gained or lost
one or more electrons and so developed an electrical charge. Ions behave
differently from electrically neutral atoms and molecules. They can move in
an electric field, and they can also bind strongly to solvent molecules such
as water. Positively charged ions are called cations; negatively charged
ions are called anions. Ions can carry an electrical current through
solutions.
Isotope - correct answer one of two or more atoms of the same element
that have the same number of protons in their nucleus (atomic number), but
which have a different number of neutrons (atomic mass). Example;
carbon-12 and carbon-14.
, Kinetic energy - correct answer the energy an object has by virtue of its
being in motion.
Latent heat - correct answer the amount of heat that is absorbed or
released during the process of changing state between gas, liquid or solid.
For example, heat is absorbed when a substance melts and it is released
again when the substance solidifies.
Liquid/liquid phase - correct answer a form of matter that has a fixed
volume but not fixed shape
Mass - correct answer the amount of matter in an object. In everyday use
the word weight is often used (somewhat incorrectly) to mean mass.
Matter - correct answer anything that has mass and takes up space.
Melting point - correct answer the temperature at which a substance
changes state from a solid phase to a liquid phase. It is the same as
freezing point.
Metal - correct answer a class of elements that is good conductor of
electricity and heat, has metallic luster, is malleable and ductile, forms
cations and has oxides that are bases. Metals are formed as cations held
together by a sea of electrons. A metal may also be an alloy of these
elements. Example sodium, calcium, gold.
Mixture - correct answer a material that can be separated into two or more
substances using physical means. Example: a mixture of copper (ii) sulfate
and cadmium sulfide can be separated by filtration.
