Grade 12 Chemistry Exam Questions
and Answers
Thermochemistry - correct answer-Branch of chemistry that studies the energy
chamges in chemical reactions.
Thermal Kinetic Energy - correct answer-Motion of particles (either atoms or molecules).
Chemical Potential Energy (CPE) - correct answer-Stored energy in the bonds between
atoms in a molecule.
Three types of motions of particles - correct answer-1. Vibration
2. Rotation
3. Translation
Temperature - correct answer-The average kinetic energy of the particles in a
substance.
Thermal Energy - correct answer-The total kinetic energy of the particles in a substance
due to their motion.
What does thermal energy depend on? - correct answer-1. The amount of moles- the
more particles there are the greater the thermal energy.
2. The speed (temperature)- the faster the particles are moving, the greater the thermal
energy.
Heat (Q) - correct answer-The transfer of thermal energy from a HOT object to a COLD
object.
System - correct answer-All of the chemical components that are involved in a chemical
reaction (the reactants, the products and whatever solvents they are in).
What are the 3 systems? - correct answer-1. Open System- exchange both matter and
energy with its surrounding.
2. Closed System- exchange energy but not matter with its surrounding.
3. Isolated System- no exchange for matter or energy with its surrounding.
Surroundings - correct answer-Everything outside of the system we are studying.
What does the total amount of chemical potential energy depend on? - correct answer-
1. The number of bonds- the more bonds a molecule has, the more energy it can store.
and Answers
Thermochemistry - correct answer-Branch of chemistry that studies the energy
chamges in chemical reactions.
Thermal Kinetic Energy - correct answer-Motion of particles (either atoms or molecules).
Chemical Potential Energy (CPE) - correct answer-Stored energy in the bonds between
atoms in a molecule.
Three types of motions of particles - correct answer-1. Vibration
2. Rotation
3. Translation
Temperature - correct answer-The average kinetic energy of the particles in a
substance.
Thermal Energy - correct answer-The total kinetic energy of the particles in a substance
due to their motion.
What does thermal energy depend on? - correct answer-1. The amount of moles- the
more particles there are the greater the thermal energy.
2. The speed (temperature)- the faster the particles are moving, the greater the thermal
energy.
Heat (Q) - correct answer-The transfer of thermal energy from a HOT object to a COLD
object.
System - correct answer-All of the chemical components that are involved in a chemical
reaction (the reactants, the products and whatever solvents they are in).
What are the 3 systems? - correct answer-1. Open System- exchange both matter and
energy with its surrounding.
2. Closed System- exchange energy but not matter with its surrounding.
3. Isolated System- no exchange for matter or energy with its surrounding.
Surroundings - correct answer-Everything outside of the system we are studying.
What does the total amount of chemical potential energy depend on? - correct answer-
1. The number of bonds- the more bonds a molecule has, the more energy it can store.
