Energetics of Biological Reactions and ATP - MCAT Chemical and Physical Foundations of Biological Systems

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Question

ATP stores energy through its ability to lose a phosphate group to form ADP in the following reaction

$ATP + $H_{2}$O \rightarrow ADP + phosphate$

At body temperature, the thermodynamic values for ATP hydrolysis are as follow.
$\Delta G=-30$\frac{kJ}{mol}$$
$\Delta H=-20$\frac{kJ}{mol}$$
$\Delta S=34$\frac{kJ}{mol}$$

Glycolysis is an energy-liberating process ( $\Delta G=-218$\frac{kJ}{mol}$$ , $\Delta H=-20$\frac{kJ}{mol}$$ ) that is coupled with the conversion of two ADP molecules into two ATP molecules according to the following reaction.

$Glucose + 2ADP + 2 phosphate \rightarrow 2 lactate + 2ATP + $2H_{2}$O$

Glycolysis results in which of the following?

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Answer

Since glycolysis is an exothermic reaction (ΔH is negative), enthalpy does not increase. As for entropy, the reaction begins with a large molecule and ends with smaller molecules, therefore entropy increases.

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Question

$C_$6H_{12}$O_6+O_2\rightarrow CO_2+H_2O$

Which of the following is true, assuming the reaction goes to completion?

I. There is an increase in $\DeltaS$ $\Delta S$ , entropy

II. $\Delta H < 0$

III. At equilibrium, $\Delta G = 0$

IV. Oxygen is the reducing agent

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Answer

This question ties together the reaction for oxidation of glucose with several thermodynamic principles.

The first option, stating that there is an increase of entropy, is true. When balanced, we see that there is an increase in total number of molecules when the reaction completes; thus, there will be an increase in entropy.

The second option states that enthalpy, or $\Delta H$ , is less than than zero. This is also true, as it implies that this is an exothermic (or heat generating) reaction. The oxidation of glucose is how our bodies generate heat and keep homeostasis.

The third option, stating that Gibb's free energy is zero at equilibrium, is also true. Any equation will have $\Delta G = 0$ at equilibrium.

The last option, stating that oxygen is the reducing agent, is false. Oxygen is actually the oxidizing agent and is itself reduced.

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Question

Adenosine-triphosphate is formed by the following endothermic reaction.

$ADP(aq) + P_i(aq) + $H^{+}$(aq) \rightarrow ATP(aq) + $H_{2}$O(l)$
If body temperature decreases, ADP production .

Tap to reveal answer

Answer

Since heat can be considered a reactant (endothermic), if heat is decreased, ADP is increased according to Le Chatelier’s Principle. If a reactant is removed, the equilibrium will shift toward the reactants. In this reaction, ADP and heat are both reactants.

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Question

ATP stores energy through its ability to lose a phosphate group to form ADP in the following reaction

$ATP + $H_{2}$O \rightarrow ADP + phosphate$

At body temperature, the thermodynamic values for ATP hydrolysis are as follow.
ΔG = –30kJ/mol
ΔH = –20kJ/mol
ΔS = 34kJ/mol

Glycolysis is an energy-liberating process (ΔG = –218kJ/mol, ΔH = –20 kJ/mol) that is coupled with the conversion of two ADP molecules into two ATP molecules according to the following reaction.

$Glucose + 2ADP + 2 phosphate \rightarrow 2 lactate + 2ATP + $2H_{2}$O$

Glycolysis is .

Tap to reveal answer

Answer

ΔG and ΔH are both negative for glycolysis, meaning that the reaction is exergonic and exothermic.

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Question

ATP stores energy through its ability to lose a phosphate group to form ADP in the following reaction

$ATP + $H_{2}$O \rightarrow ADP + phosphate$

At body temperature, the thermodynamic values for ATP hydrolysis are as follow.
ΔG = –30kJ/mol
ΔH = –20kJ/mol
ΔS = 34kJ/mol

Glycolysis is an energy-liberating process (ΔG = –218kJ/mol, ΔH = –20 kJ/mol) that is coupled with the conversion of two ADP molecules into two ATP molecules according to the following reaction.

$Glucose + 2ADP + 2 phosphate \rightarrow 2 lactate + 2ATP + $2H_{2}$O$

How much heat, in joules, is released when 4 * 1019 molecules of ATP are converted to ADP via ATP hydrolysis?

Tap to reveal answer

Answer

To solve this problem, first convert molecules to moles with Avogadro’s number, then convert moles to kJ using the ΔH of ATP hydrolysis. Lastly convert kJ to J.

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Question

ATP stores energy through its ability to lose a phosphate group to form ADP in the following reaction

$ATP + $H_{2}$O \rightarrow ADP + phosphate$

At body temperature, the thermodynamic values for ATP hydrolysis are as follow.
ΔG = –30kJ/mol
ΔH = –20kJ/mol
ΔS = 34kJ/mol

Glycolysis is an energy-liberating process (ΔG = –218kJ/mol, ΔH = –20 kJ/mol) that is coupled with the conversion of two ADP molecules into two ATP molecules according to the following reaction.

$Glucose + 2ADP + 2 phosphate \rightarrow 2 lactate + 2ATP + $2H_{2}$O$

The formation of peptide bonds requires 17kJ/mol of energy. It also requires the energy of three ATP molecules. How many ATP molecules are required to synthesize a protein containing 550 peptide bonds?

Tap to reveal answer

Answer

Since we know that three ATP molecules per bond are required, 1,650 ATP molecules are needed. However, we also know that 17kJ/mol of additional energy is required for each bond. This energy must come from ATP molecules. The only choice that is greater than 1,650 is 1,962.

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Question

$C_$6H_{12}$O_6+O_2\rightarrow CO_2+H_2O$

Which of the following is true, assuming the reaction goes to completion?

I. There is an increase in $\DeltaS$ $\Delta S$ , entropy

II. $\Delta H < 0$

III. At equilibrium, $\Delta G = 0$

IV. Oxygen is the reducing agent

Tap to reveal answer

Answer

This question ties together the reaction for oxidation of glucose with several thermodynamic principles.

The first option, stating that there is an increase of entropy, is true. When balanced, we see that there is an increase in total number of molecules when the reaction completes; thus, there will be an increase in entropy.

The second option states that enthalpy, or $\Delta H$ , is less than than zero. This is also true, as it implies that this is an exothermic (or heat generating) reaction. The oxidation of glucose is how our bodies generate heat and keep homeostasis.

The third option, stating that Gibb's free energy is zero at equilibrium, is also true. Any equation will have $\Delta G = 0$ at equilibrium.

The last option, stating that oxygen is the reducing agent, is false. Oxygen is actually the oxidizing agent and is itself reduced.

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Question

Adenosine-triphosphate is formed by the following endothermic reaction.

$ADP(aq) + P_i(aq) + $H^{+}$(aq) \rightarrow ATP(aq) + $H_{2}$O(l)$
If body temperature decreases, ADP production .

Tap to reveal answer

Answer

Since heat can be considered a reactant (endothermic), if heat is decreased, ADP is increased according to Le Chatelier’s Principle. If a reactant is removed, the equilibrium will shift toward the reactants. In this reaction, ADP and heat are both reactants.

← Didn't Know|Knew It →

Question

ATP stores energy through its ability to lose a phosphate group to form ADP in the following reaction

$ATP + $H_{2}$O \rightarrow ADP + phosphate$

At body temperature, the thermodynamic values for ATP hydrolysis are as follow.
ΔG = –30kJ/mol
ΔH = –20kJ/mol
ΔS = 34kJ/mol

Glycolysis is an energy-liberating process (ΔG = –218kJ/mol, ΔH = –20 kJ/mol) that is coupled with the conversion of two ADP molecules into two ATP molecules according to the following reaction.

$Glucose + 2ADP + 2 phosphate \rightarrow 2 lactate + 2ATP + $2H_{2}$O$

Glycolysis is .

Tap to reveal answer

Answer

ΔG and ΔH are both negative for glycolysis, meaning that the reaction is exergonic and exothermic.

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Question

ATP stores energy through its ability to lose a phosphate group to form ADP in the following reaction

$ATP + $H_{2}$O \rightarrow ADP + phosphate$

At body temperature, the thermodynamic values for ATP hydrolysis are as follow.
ΔG = –30kJ/mol
ΔH = –20kJ/mol
ΔS = 34kJ/mol

Glycolysis is an energy-liberating process (ΔG = –218kJ/mol, ΔH = –20 kJ/mol) that is coupled with the conversion of two ADP molecules into two ATP molecules according to the following reaction.

$Glucose + 2ADP + 2 phosphate \rightarrow 2 lactate + 2ATP + $2H_{2}$O$

How much heat, in joules, is released when 4 * 1019 molecules of ATP are converted to ADP via ATP hydrolysis?

Tap to reveal answer

Answer

To solve this problem, first convert molecules to moles with Avogadro’s number, then convert moles to kJ using the ΔH of ATP hydrolysis. Lastly convert kJ to J.

← Didn't Know|Knew It →

Question

ATP stores energy through its ability to lose a phosphate group to form ADP in the following reaction

$ATP + $H_{2}$O \rightarrow ADP + phosphate$

At body temperature, the thermodynamic values for ATP hydrolysis are as follow.
$\Delta G=-30$\frac{kJ}{mol}$$
$\Delta H=-20$\frac{kJ}{mol}$$
$\Delta S=34$\frac{kJ}{mol}$$

Glycolysis is an energy-liberating process ( $\Delta G=-218$\frac{kJ}{mol}$$ , $\Delta H=-20$\frac{kJ}{mol}$$ ) that is coupled with the conversion of two ADP molecules into two ATP molecules according to the following reaction.

$Glucose + 2ADP + 2 phosphate \rightarrow 2 lactate + 2ATP + $2H_{2}$O$

Glycolysis results in which of the following?

Tap to reveal answer

Answer

Since glycolysis is an exothermic reaction (ΔH is negative), enthalpy does not increase. As for entropy, the reaction begins with a large molecule and ends with smaller molecules, therefore entropy increases.

← Didn't Know|Knew It →

Question

ATP stores energy through its ability to lose a phosphate group to form ADP in the following reaction

$ATP + $H_{2}$O \rightarrow ADP + phosphate$

At body temperature, the thermodynamic values for ATP hydrolysis are as follow.
ΔG = –30kJ/mol
ΔH = –20kJ/mol
ΔS = 34kJ/mol

Glycolysis is an energy-liberating process (ΔG = –218kJ/mol, ΔH = –20 kJ/mol) that is coupled with the conversion of two ADP molecules into two ATP molecules according to the following reaction.

$Glucose + 2ADP + 2 phosphate \rightarrow 2 lactate + 2ATP + $2H_{2}$O$

The formation of peptide bonds requires 17kJ/mol of energy. It also requires the energy of three ATP molecules. How many ATP molecules are required to synthesize a protein containing 550 peptide bonds?

Tap to reveal answer

Answer

Since we know that three ATP molecules per bond are required, 1,650 ATP molecules are needed. However, we also know that 17kJ/mol of additional energy is required for each bond. This energy must come from ATP molecules. The only choice that is greater than 1,650 is 1,962.

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Question

$C_$6H_{12}$O_6+O_2\rightarrow CO_2+H_2O$

Which of the following is true, assuming the reaction goes to completion?

I. There is an increase in $\DeltaS$ $\Delta S$ , entropy

II. $\Delta H < 0$

III. At equilibrium, $\Delta G = 0$

IV. Oxygen is the reducing agent

Tap to reveal answer

Answer

This question ties together the reaction for oxidation of glucose with several thermodynamic principles.

The first option, stating that there is an increase of entropy, is true. When balanced, we see that there is an increase in total number of molecules when the reaction completes; thus, there will be an increase in entropy.

The second option states that enthalpy, or $\Delta H$ , is less than than zero. This is also true, as it implies that this is an exothermic (or heat generating) reaction. The oxidation of glucose is how our bodies generate heat and keep homeostasis.

The third option, stating that Gibb's free energy is zero at equilibrium, is also true. Any equation will have $\Delta G = 0$ at equilibrium.

The last option, stating that oxygen is the reducing agent, is false. Oxygen is actually the oxidizing agent and is itself reduced.

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Question

Adenosine-triphosphate is formed by the following endothermic reaction.

$ADP(aq) + P_i(aq) + $H^{+}$(aq) \rightarrow ATP(aq) + $H_{2}$O(l)$
If body temperature decreases, ADP production .

Tap to reveal answer

Answer

Since heat can be considered a reactant (endothermic), if heat is decreased, ADP is increased according to Le Chatelier’s Principle. If a reactant is removed, the equilibrium will shift toward the reactants. In this reaction, ADP and heat are both reactants.

← Didn't Know|Knew It →

Question

ATP stores energy through its ability to lose a phosphate group to form ADP in the following reaction

$ATP + $H_{2}$O \rightarrow ADP + phosphate$

At body temperature, the thermodynamic values for ATP hydrolysis are as follow.
ΔG = –30kJ/mol
ΔH = –20kJ/mol
ΔS = 34kJ/mol

Glycolysis is an energy-liberating process (ΔG = –218kJ/mol, ΔH = –20 kJ/mol) that is coupled with the conversion of two ADP molecules into two ATP molecules according to the following reaction.

$Glucose + 2ADP + 2 phosphate \rightarrow 2 lactate + 2ATP + $2H_{2}$O$

Glycolysis is .

Tap to reveal answer

Answer

ΔG and ΔH are both negative for glycolysis, meaning that the reaction is exergonic and exothermic.

← Didn't Know|Knew It →

Question

ATP stores energy through its ability to lose a phosphate group to form ADP in the following reaction

$ATP + $H_{2}$O \rightarrow ADP + phosphate$

At body temperature, the thermodynamic values for ATP hydrolysis are as follow.
ΔG = –30kJ/mol
ΔH = –20kJ/mol
ΔS = 34kJ/mol

Glycolysis is an energy-liberating process (ΔG = –218kJ/mol, ΔH = –20 kJ/mol) that is coupled with the conversion of two ADP molecules into two ATP molecules according to the following reaction.

$Glucose + 2ADP + 2 phosphate \rightarrow 2 lactate + 2ATP + $2H_{2}$O$

How much heat, in joules, is released when 4 * 1019 molecules of ATP are converted to ADP via ATP hydrolysis?

Tap to reveal answer

Answer

To solve this problem, first convert molecules to moles with Avogadro’s number, then convert moles to kJ using the ΔH of ATP hydrolysis. Lastly convert kJ to J.

← Didn't Know|Knew It →

Question

ATP stores energy through its ability to lose a phosphate group to form ADP in the following reaction

$ATP + $H_{2}$O \rightarrow ADP + phosphate$

At body temperature, the thermodynamic values for ATP hydrolysis are as follow.
$\Delta G=-30$\frac{kJ}{mol}$$
$\Delta H=-20$\frac{kJ}{mol}$$
$\Delta S=34$\frac{kJ}{mol}$$

Glycolysis is an energy-liberating process ( $\Delta G=-218$\frac{kJ}{mol}$$ , $\Delta H=-20$\frac{kJ}{mol}$$ ) that is coupled with the conversion of two ADP molecules into two ATP molecules according to the following reaction.

$Glucose + 2ADP + 2 phosphate \rightarrow 2 lactate + 2ATP + $2H_{2}$O$

Glycolysis results in which of the following?

Tap to reveal answer

Answer

Since glycolysis is an exothermic reaction (ΔH is negative), enthalpy does not increase. As for entropy, the reaction begins with a large molecule and ends with smaller molecules, therefore entropy increases.

← Didn't Know|Knew It →

Question

ATP stores energy through its ability to lose a phosphate group to form ADP in the following reaction

$ATP + $H_{2}$O \rightarrow ADP + phosphate$

At body temperature, the thermodynamic values for ATP hydrolysis are as follow.
ΔG = –30kJ/mol
ΔH = –20kJ/mol
ΔS = 34kJ/mol

Glycolysis is an energy-liberating process (ΔG = –218kJ/mol, ΔH = –20 kJ/mol) that is coupled with the conversion of two ADP molecules into two ATP molecules according to the following reaction.

$Glucose + 2ADP + 2 phosphate \rightarrow 2 lactate + 2ATP + $2H_{2}$O$

The formation of peptide bonds requires 17kJ/mol of energy. It also requires the energy of three ATP molecules. How many ATP molecules are required to synthesize a protein containing 550 peptide bonds?

Tap to reveal answer

Answer

Since we know that three ATP molecules per bond are required, 1,650 ATP molecules are needed. However, we also know that 17kJ/mol of additional energy is required for each bond. This energy must come from ATP molecules. The only choice that is greater than 1,650 is 1,962.

← Didn't Know|Knew It →

Question

ATP stores energy through its ability to lose a phosphate group to form ADP in the following reaction

$ATP + $H_{2}$O \rightarrow ADP + phosphate$

At body temperature, the thermodynamic values for ATP hydrolysis are as follow.
$\Delta G=-30$\frac{kJ}{mol}$$
$\Delta H=-20$\frac{kJ}{mol}$$
$\Delta S=34$\frac{kJ}{mol}$$

Glycolysis is an energy-liberating process ( $\Delta G=-218$\frac{kJ}{mol}$$ , $\Delta H=-20$\frac{kJ}{mol}$$ ) that is coupled with the conversion of two ADP molecules into two ATP molecules according to the following reaction.

$Glucose + 2ADP + 2 phosphate \rightarrow 2 lactate + 2ATP + $2H_{2}$O$

Glycolysis results in which of the following?

Tap to reveal answer

Answer

Since glycolysis is an exothermic reaction (ΔH is negative), enthalpy does not increase. As for entropy, the reaction begins with a large molecule and ends with smaller molecules, therefore entropy increases.

← Didn't Know|Knew It →

Question

$C_$6H_{12}$O_6+O_2\rightarrow CO_2+H_2O$

Which of the following is true, assuming the reaction goes to completion?

I. There is an increase in $\DeltaS$ $\Delta S$ , entropy

II. $\Delta H < 0$

III. At equilibrium, $\Delta G = 0$

IV. Oxygen is the reducing agent

Tap to reveal answer

Answer

This question ties together the reaction for oxidation of glucose with several thermodynamic principles.

The first option, stating that there is an increase of entropy, is true. When balanced, we see that there is an increase in total number of molecules when the reaction completes; thus, there will be an increase in entropy.

The second option states that enthalpy, or $\Delta H$ , is less than than zero. This is also true, as it implies that this is an exothermic (or heat generating) reaction. The oxidation of glucose is how our bodies generate heat and keep homeostasis.

The third option, stating that Gibb's free energy is zero at equilibrium, is also true. Any equation will have $\Delta G = 0$ at equilibrium.

The last option, stating that oxygen is the reducing agent, is false. Oxygen is actually the oxidizing agent and is itself reduced.

← Didn't Know|Knew It →

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Energetics of Biological Reactions and ATP - MCAT Chemical and Physical Foundations of Biological Systems

Since glycolysis is an exothermic reaction (ΔH is negative), enthalpy does not increase. As for entropy, the reaction begins with a large molecule and ends with smaller molecules, therefore entropy increases.

Which of the following is true, assuming the reaction goes to completion? I. There is an increase in , entropy II. III. At equilibrium, IV. Oxygen is the reducing agent

Adenosine-triphosphate is formed by the following endothermic reaction. If body temperature decreases, ADP production .

Since heat can be considered a reactant (endothermic), if heat is decreased, ADP is increased according to Le Chatelier’s Principle. If a reactant is removed, the equilibrium will shift toward the reactants. In this reaction, ADP and heat are both reactants.

ΔG and ΔH are both negative for glycolysis, meaning that the reaction is exergonic and exothermic.

To solve this problem, first convert molecules to moles with Avogadro’s number, then convert moles to kJ using the ΔH of ATP hydrolysis. Lastly convert kJ to J.

Since we know that three ATP molecules per bond are required, 1,650 ATP molecules are needed. However, we also know that 17kJ/mol of additional energy is required for each bond. This energy must come from ATP molecules. The only choice that is greater than 1,650 is 1,962.

Which of the following is true, assuming the reaction goes to completion? I. There is an increase in , entropy II. III. At equilibrium, IV. Oxygen is the reducing agent

Adenosine-triphosphate is formed by the following endothermic reaction. If body temperature decreases, ADP production .

Since heat can be considered a reactant (endothermic), if heat is decreased, ADP is increased according to Le Chatelier’s Principle. If a reactant is removed, the equilibrium will shift toward the reactants. In this reaction, ADP and heat are both reactants.

ΔG and ΔH are both negative for glycolysis, meaning that the reaction is exergonic and exothermic.

To solve this problem, first convert molecules to moles with Avogadro’s number, then convert moles to kJ using the ΔH of ATP hydrolysis. Lastly convert kJ to J.

Since glycolysis is an exothermic reaction (ΔH is negative), enthalpy does not increase. As for entropy, the reaction begins with a large molecule and ends with smaller molecules, therefore entropy increases.

Since we know that three ATP molecules per bond are required, 1,650 ATP molecules are needed. However, we also know that 17kJ/mol of additional energy is required for each bond. This energy must come from ATP molecules. The only choice that is greater than 1,650 is 1,962.

Which of the following is true, assuming the reaction goes to completion? I. There is an increase in , entropy II. III. At equilibrium, IV. Oxygen is the reducing agent

Adenosine-triphosphate is formed by the following endothermic reaction. If body temperature decreases, ADP production .

Since heat can be considered a reactant (endothermic), if heat is decreased, ADP is increased according to Le Chatelier’s Principle. If a reactant is removed, the equilibrium will shift toward the reactants. In this reaction, ADP and heat are both reactants.

ΔG and ΔH are both negative for glycolysis, meaning that the reaction is exergonic and exothermic.

To solve this problem, first convert molecules to moles with Avogadro’s number, then convert moles to kJ using the ΔH of ATP hydrolysis. Lastly convert kJ to J.

Since glycolysis is an exothermic reaction (ΔH is negative), enthalpy does not increase. As for entropy, the reaction begins with a large molecule and ends with smaller molecules, therefore entropy increases.

Since we know that three ATP molecules per bond are required, 1,650 ATP molecules are needed. However, we also know that 17kJ/mol of additional energy is required for each bond. This energy must come from ATP molecules. The only choice that is greater than 1,650 is 1,962.

Since glycolysis is an exothermic reaction (ΔH is negative), enthalpy does not increase. As for entropy, the reaction begins with a large molecule and ends with smaller molecules, therefore entropy increases.

Which of the following is true, assuming the reaction goes to completion? I. There is an increase in , entropy II. III. At equilibrium, IV. Oxygen is the reducing agent

$C_$6H_{12}$O_6+O_2\rightarrow CO_2+H_2O$

Which of the following is true, assuming the reaction goes to completion?

I. There is an increase in $\DeltaS$ $\Delta S$ , entropy

II. $\Delta H < 0$

III. At equilibrium, $\Delta G = 0$

IV. Oxygen is the reducing agent

Adenosine-triphosphate is formed by the following endothermic reaction.

$ADP(aq) + P_i(aq) + $H^{+}$(aq) \rightarrow ATP(aq) + $H_{2}$O(l)$
If body temperature decreases, ADP production .

$C_$6H_{12}$O_6+O_2\rightarrow CO_2+H_2O$

Which of the following is true, assuming the reaction goes to completion?

I. There is an increase in $\DeltaS$ $\Delta S$ , entropy

II. $\Delta H < 0$

III. At equilibrium, $\Delta G = 0$

IV. Oxygen is the reducing agent

Adenosine-triphosphate is formed by the following endothermic reaction.

$ADP(aq) + P_i(aq) + $H^{+}$(aq) \rightarrow ATP(aq) + $H_{2}$O(l)$
If body temperature decreases, ADP production .

$C_$6H_{12}$O_6+O_2\rightarrow CO_2+H_2O$

Which of the following is true, assuming the reaction goes to completion?

I. There is an increase in $\DeltaS$ $\Delta S$ , entropy

II. $\Delta H < 0$

III. At equilibrium, $\Delta G = 0$

IV. Oxygen is the reducing agent

Adenosine-triphosphate is formed by the following endothermic reaction.

$ADP(aq) + P_i(aq) + $H^{+}$(aq) \rightarrow ATP(aq) + $H_{2}$O(l)$
If body temperature decreases, ADP production .

$C_$6H_{12}$O_6+O_2\rightarrow CO_2+H_2O$

Which of the following is true, assuming the reaction goes to completion?

I. There is an increase in $\DeltaS$ $\Delta S$ , entropy

II. $\Delta H < 0$

III. At equilibrium, $\Delta G = 0$

IV. Oxygen is the reducing agent