A Level Chemistry Energetics

Q1.

Which of the following is the most accurate definition of Bond Enthalpy (B)?

1. Bond enthalpy is the amount of energy required to break one mole of a specific covalent bond in the gas phase
2. Bond enthalpy is the amount of energy required to break one mole of a specific covalent bond in the liquid phase

Q2.

Hess's law states that the Standard Enthalpy of a reaction is:

1. equal to the Standard Enthalpies of all the steps
2. not always equal to the Standard Enthalpies of all the steps

Q3.

In chemical energetics, we only care about which of the following forms of energy? (select all applicable)

1. Heat energy
2. Mechanical energy
3. Chemical energy
4. Electrical energy

Q4.

Which of the following is the most accurate definition of Enthalpy change (ΔH)?

1. Enthalpy change is the amount of heat energy absorbed or released in a chemical reaction
2. Enthalpy change is the amount of heat energy absorbed or released in a chemical reaction under constant pressure

Q5.

Which one of the following correctly describes the formula for calculating overall Enthalpy change?

1. Overall Enthalpy change = energy to break bonds - energy to make bonds
2. Overall Enthalpy change = energy to break bonds + energy to make bonds

Q6.

Which one of the following describes Calorimetry best?

1. Calorimetry is an experimental method for finding enthalpy change by measuring change in temperature over time
2. Calorimetry is a theoretical model used for predicting the rate of a reaction

Q7.

Which of the following most accurately defines Enthalpy (H)?

1. Enthalpy is the amount of thermal energy stored in a system
2. Enthalpy is the property of a system that determines how quick a reaction can be
3. Enthalpy is a property of catalysts that speed up a chemical reaction

Q8.

Which of the following describes Energetics most accurately?

1. Energetics is mainly concerned with how quick a chemical reaction is
2. Energetics is the study of flow of energy in chemical reactions
3. Energetics is the study of chemical reactions that use catalysts

Q9.

When a reaction absorbs energy, the total enthalpy of the system increases. True of false?

1. True
2. False

Q10.

It not possible to directly measure the total enthalpy in a system; however, we can measure the changes in enthalpy that take place in a chemical reaction. True or false?

1. True
2. False

Subject: Chemistry

Level: Medium