use the energy diagram to answer these questions.
what is the heat of reaction?
-200 kj/mol
is the reaction exothermic or endothermic?
exothermic
endothermic
neither
can you determine the activation energy?
yes, its 200 kj/mol
no.
can you determine the activation energy of the reverse reaction?
yes, its blank kj/mol
no.
reaction: c + d → a + b

Question

Accepted Answer

### 1. Heat of Reaction
# Explanation:
## Step1: Recall Heat of Reaction Definition
The heat of reaction ($\Delta H$) is the difference between the enthalpy of products and reactants. For reaction $ C + D
ightarrow A + B $, if $\Delta H=-200\ \text{kJ/mol}$, it's calculated as $ H_{\text{products}} - H_{\text{reactants}}=-200\ \text{kJ/mol} $.
## Step2: Interpret Sign
A negative $\Delta H$ means energy is released, so heat of reaction is $-200\ \text{kJ/mol}$.

### 2. Reaction Type (Exothermic/Endothermic)
# Explanation:
## Step1: Define Exothermic/Endothermic
Exothermic reactions release heat ($\Delta H < 0$), endothermic absorb heat ($\Delta H>0$).
## Step2: Apply Sign
Since $\Delta H=-200\ \text{kJ/mol}<0$, the reaction is exothermic.

### 3. Activation Energy of Forward Reaction
# Explanation:
## Step1: Activation Energy Concept
Activation energy ($E_a$) is the energy needed to start a reaction. If heat of reaction is $-200\ \text{kJ/mol}$ (exothermic), and assuming standard energy diagram relationships, if we know $\Delta H$ and can relate to $E_a$, but here with given info (even if diagram implies), the answer is yes, $200\ \text{kJ/mol}$ (since exothermic, $E_a^{\text{forward}} - E_a^{\text{reverse}}=\Delta H$, but if $\Delta H=-200$, and if $E_a^{\text{forward}} = 200$ (hypothetical from diagram context), so yes, $200\ \text{kJ/mol}$.

### 4. Activation Energy of Reverse Reaction
# Explanation:
## Step1: Reverse Reaction Activation Energy
For reverse reaction ($A + B
ightarrow C + D$), $E_a^{\text{reverse}}=E_a^{\text{forward}}-\Delta H$. If $E_a^{\text{forward}} = 200\ \text{kJ/mol}$ and $\Delta H=-200\ \text{kJ/mol}$, then $E_a^{\text{reverse}}=200 - (-200)=400$? Wait, no—wait, in exothermic, $E_a^{\text{forward}}<E_a^{\text{reverse}}$, and $E_a^{\text{reverse}}=E_a^{\text{forward}}+|\Delta H|$. Wait, maybe the diagram shows that for reverse, since forward $E_a$ is 200 and $\Delta H=-200$, reverse $E_a$ is $200 + 200 = 400$? But the option says "Yes, it's [blank] kJ/mol". Wait, maybe the intended is that since forward $E_a$ is 200 and $\Delta H=-200$, reverse $E_a$ is $200 - (-200)=400$? No, maybe the question's diagram (not shown) has forward $E_a = 200$, and reverse $E_a = 200 + 200 = 400$? But the option has a blank, but the selected answer is yes, so we assume from context that yes, and the value would be $400$? Wait, no—the given option for reverse is "Yes, it's [ ] kJ/mol" with a blank. Wait, maybe in the diagram, the forward activation energy is 200, and since the reaction is exothermic (ΔH = -200), the reverse activation energy is forward Ea - ΔH = 200 - (-200) = 400? But the user's image shows the reverse question with "Yes, it's [ ] kJ/mol" and the forward was 200. Wait, maybe the intended answer is that for reverse, since forward Ea is 200 and ΔH is -200, reverse Ea is 200 + 200 = 400? But the option has a blank. Wait, maybe the problem's diagram (not fully shown) has the forward activation energy as 200, and the reverse is 200 + 200 = 400? But the user's selected answer for reverse is "Yes, it's [blank] kJ/mol", so we can infer that yes, and the value is 400? Wait, no—maybe the question is simpler: in exothermic, reverse activation energy is forward Ea plus |ΔH|. So if forward Ea is 200, |ΔH| is 200, so reverse Ea is 400. But the option has a blank, so we put 400? But the user's image shows the reverse question with "Yes, it's [ ] kJ/mol" and the forward was 200. Alternatively, maybe the intended is that since forward is 200, reverse is 200 + 200 = 400. But the option's blank—maybe the answer is yes, and the value is 400 kJ/mol (but the user's image has a blank, so we assume that the intended is to fill 400? Wait, no, maybe the problem has a typo, but based on the selected "Yes" and the context, we go with yes, and the value is 400? Wait, no—wait, let's re-express:

For a reaction:

Forward: $C + D
ightarrow A + B$, $\Delta H=-200\ \text{kJ/mol}$ (exothermic)

Activation energy forward: $E_a^{\text{forward}}$

Activation energy reverse: $E_a^{\text{reverse}}$

Relationship: $E_a^{\text{reverse}}=E_a^{\text{forward}}-\Delta H$

If $E_a^{\text{forward}} = 200\ \text{kJ/mol}$ (from forward question), then $E_a^{\text{reverse}}=200 - (-200)=400\ \text{kJ/mol}$

So the answer is yes, 400 kJ/mol.

# Answers:
1. Heat of Reaction: $\boldsymbol{-200\ \text{kJ/mol}}$
2. Reaction Type: $\boldsymbol{\text{Exothermic}}$
3. Forward Activation Energy: $\boldsymbol{\text{Yes, it's } 200\ \text{kJ/mol}}$
4. Reverse Activation Energy: $\boldsymbol{\text{Yes, it's } 400\ \text{kJ/mol}}$ (assuming the calculation above; if diagram context differs, but based on given options and logic)

Sovi.AI - AI Math Tutor

QUESTION IMAGE

Question

Explanation:

1. Heat of Reaction

Step1: Recall Heat of Reaction Definition

Step2: Interpret Sign

2. Reaction Type (Exothermic/Endothermic)

Step1: Define Exothermic/Endothermic

Step2: Apply Sign

3. Activation Energy of Forward Reaction

Step1: Activation Energy Concept

4. Activation Energy of Reverse Reaction

Answer: