Energy and Change Gr 11

Which example best describes a physical change?

• iron rusting
• charcoal burning
• an ice cube melting
• a marshmallow burning

Sodium Hydroxide dissolves in water

• Chemical Change
• Physical Change

Hydrochloric acid reacts with potassium hydroxide to produce a salt, water,and heat.

• Chemical Change
• Physical Change

Which of the following statements concerning this graph is INCORRECT?

• More energy is absorbed than released.

• More energy is released than absorbed.

• The reactants have less energy than the products.

• The products have more energy than the reactants.

Which combination is CORRECT for this reaction?

• A

• B

• C

• D

Consider the reaction represented by the equation below:

2Fe(s) + 3CO₂(g) → Fe₂O₃(s) + 2CO(g) ΔH = + 53,2 kJ

Which ONE of the following statements is TRUE?

For each mole of Fe that reacts, …

• 26,6 kJ of energy are released.

• 26,6 kJ of energy are absorbed.

• 53,2 kJ of energy are released.

• 53,2 kJ of energy are absorbed.

Consider the combustion of 1 mol methane:

CH₄ + 2O₂ → CO₂+ 2H₂O

What is the total amount of energy required to break all the bonds in 1 mol CH₄ and 2 mol O₂?

Write your answer in kJ.

Consider the combustion of 1 mol methane:

CH₄ + 2O₂ → CO₂+ 2H₂O

How much energy is released when bonds form to produce 2 mol of H₂O and 1 mol of CO₂?

Write your answer in kJ.

Consider the combustion of 1 mol methane:

CH₄ + 2O₂ → CO₂+ 2H₂O

Calculate the energy transferred (ΔH) for the combustion of 1 mol CH₄.

Write your answer in kJ.

• A

• B

• C

• D