A-Level Chemistry Introduction to Enthalpy

1. To measure the change in pressure

2. To measure the change in thermal energy (the temperature)

3. To use a catalyst

4. To keep the volume of the reactants and the products constant

1. equal to zero

2. less than zero

3. greater than zero

4. none of the above

1. It is a specific reference state for a substance defined by standard conditions of temperature and pressure.

2. It is the amount of heat energy required to make a chemical reaction take place under standard conditions.

3. It is the amount of energy transferred when a chemical reaction takes place under standard conditions.

1. the mechanical energy, temperature

2. the mechanical energy, pressure

3. the heat energy, volume

4. the heat energy, pressure

1. Pressure 1 KPa, and Temperature 298 °C

2. Pressure 100 KPa, and Temperature 298 °C

3. Pressure 100 Pa, and Temperature 298 K

4. Pressure 100 KPa, and Temperature 298 K

5. Pressure 100 KPa, and Temperature -298 K

1. Potential energy

2. Renewable energy

3. Covalent compound

4. Molecule

1. False

2. True

1. The atoms and the bonds involved in a chemical reaction.

2. The components other than the atoms and the bonds involved in a chemical reaction

3. None of the above

1. Chemical bonds are formed or broken without any change in the energy.

2. Chemical bonds are the forces of attraction that bind atoms together.

3. Chemical energy cannot be converted to any other form of energy.

4. Chemical energy lies within chemical bonds.

1. greater than zero

2. less than zero

3. none of the above

4. equal to zero