Chem 103
Chem 103 Exam 1 Questions and
Answers 2026
What is chemistry? -Correct Answer ✔-Chemistry is the study of the physical and
compositional changes of matter.
Chemistry is called the Central Science.
Many health-related areas of study are based on Chemistry.
Matter -Correct Answer ✔-Matter is anything that has mass, occupies space and is
made-up of atoms or parts of atoms.
Mass -Correct Answer ✔--Mass is a measure of the amount of matter in an object.
-Mass is independent of the location of an object.
-An object on the earth has the same mass as the same object on the moon, but
not same weight.
Weight -Correct Answer ✔--Weight is a measure of gravitational force acting on
object.
-Weight depends on the location of an object.
-Force = Mass * Acceleration, F = ma, Wt = m(gravity).
-An object weighing 1.0 lb on earth, weighs about 0.17 lb on the moon. Mass of
object is constant. Moon has 1/6 gravity of earth, which reduces apparent weight
of object.
Physical Properties of Matter -Correct Answer ✔--Physical properties can be
observed or measured without changing the composition of the matter being
observed.
Examples of physical properties are: color, shape and mass, and all changes of
state like gas to a liquid.
Chem 103
, Chem 103
Chemical Properties of Matter -Correct Answer ✔--Chemical properties can be
observed or measured only when the composition of matter is changed.
Examples of chemical properties are flammability and the ability to react (e.g.
when vinegar and baking soda are mixed). Atoms must change partners.
Physical changes of Matter -Correct Answer ✔--Physical changes are reversible.
-Physical changes take place without a change in composition. Atoms are not
changing partners.
-Nothing new is being created.
Examples of physical changes are freezing, melting, or evaporation of a substance
(e.g. water). H2O(s) → H2O(l), ice → water.
Separation of compounds is a physical change.
ex/ separating iron filing from sand is a chemical reaction
Chemical Changes of matter -Correct Answer ✔--Chemical changes are not always
reversible.
-Chemical changes are always accompanied by a change in composition. Atoms
are changing partners.
-New types of matter are being created, O2 + 2H2 → 2H2O
Examples of chemical changes are the burning of paper and the fizzing of a
mixture of vinegar and baking soda.
Democritus (Greek, 460-370 BC) -Correct Answer ✔-First person whose writings
suggested,
-based only on logic, that atoms where the
basis of matter.
-Atoms comes from the word 'atomos'
means "no cut".
-Democritus said there were different types of atoms.
-Matter was made of atoms and spaces, call the void.
-Aristotle, (384-322 BC) argued against the possibility of a void and the atomic
theory was lost for nearly 1500 years.
Chem 103
Chem 103 Exam 1 Questions and
Answers 2026
What is chemistry? -Correct Answer ✔-Chemistry is the study of the physical and
compositional changes of matter.
Chemistry is called the Central Science.
Many health-related areas of study are based on Chemistry.
Matter -Correct Answer ✔-Matter is anything that has mass, occupies space and is
made-up of atoms or parts of atoms.
Mass -Correct Answer ✔--Mass is a measure of the amount of matter in an object.
-Mass is independent of the location of an object.
-An object on the earth has the same mass as the same object on the moon, but
not same weight.
Weight -Correct Answer ✔--Weight is a measure of gravitational force acting on
object.
-Weight depends on the location of an object.
-Force = Mass * Acceleration, F = ma, Wt = m(gravity).
-An object weighing 1.0 lb on earth, weighs about 0.17 lb on the moon. Mass of
object is constant. Moon has 1/6 gravity of earth, which reduces apparent weight
of object.
Physical Properties of Matter -Correct Answer ✔--Physical properties can be
observed or measured without changing the composition of the matter being
observed.
Examples of physical properties are: color, shape and mass, and all changes of
state like gas to a liquid.
Chem 103
, Chem 103
Chemical Properties of Matter -Correct Answer ✔--Chemical properties can be
observed or measured only when the composition of matter is changed.
Examples of chemical properties are flammability and the ability to react (e.g.
when vinegar and baking soda are mixed). Atoms must change partners.
Physical changes of Matter -Correct Answer ✔--Physical changes are reversible.
-Physical changes take place without a change in composition. Atoms are not
changing partners.
-Nothing new is being created.
Examples of physical changes are freezing, melting, or evaporation of a substance
(e.g. water). H2O(s) → H2O(l), ice → water.
Separation of compounds is a physical change.
ex/ separating iron filing from sand is a chemical reaction
Chemical Changes of matter -Correct Answer ✔--Chemical changes are not always
reversible.
-Chemical changes are always accompanied by a change in composition. Atoms
are changing partners.
-New types of matter are being created, O2 + 2H2 → 2H2O
Examples of chemical changes are the burning of paper and the fizzing of a
mixture of vinegar and baking soda.
Democritus (Greek, 460-370 BC) -Correct Answer ✔-First person whose writings
suggested,
-based only on logic, that atoms where the
basis of matter.
-Atoms comes from the word 'atomos'
means "no cut".
-Democritus said there were different types of atoms.
-Matter was made of atoms and spaces, call the void.
-Aristotle, (384-322 BC) argued against the possibility of a void and the atomic
theory was lost for nearly 1500 years.
Chem 103
