The Mystery of the Missing Carbon

aka The Carbon Cycle

My name is Bennett. Sami Bennett.

I was in my office one night later than usual, working on a difficult case. Suddenly, in came a suspicious-looking molecule. He reminded me of my friend’s dog, who had mysteriously acquired a lame leg. I had served him, looking for clues, and finally accused the neighbor of doing the mischief. I was right, as I usually am, and the dog has been on my case ever since.

This molecule asked me if I was busy. I told him I was, but if he wanted a detective, he was looking in the right place. He took a seat and wouldn’t speak for minutes. I was about to ask him out right when he began.

I’m looking for Carbon.”

I blinked. Had I heard correctly? “Say that again, please,” I said slowly.

Carbon. I need to find Carbon.” He shifted in his seat nervously.

I gulped. I thought to myself, “Bennett, you’ve had tough cases before and you’ll have tough cases again.” Once I had gathered my courage I told the molecule, “I’ll find your Carbon. I’ve seen him before. There’s only one small difficulty.”

What’s that?” he cut in hastily.

I looked sharply at him. “Carbon… is everywhere.”

The molecule jumped, looked startled, and grabbed the armrests of his chair. I could barely make out his works. “Where?”

To help my client calm his nerves and break our scene’s tension, I casually looked around the room. I had some wood near the fireplace ready for burning. I took a break and thought hard.

I’m afraid,” I said, “you won’t like to hear this, sir, but if you look behind you, I can show you where your Carbon may have gone.”

My client (with an edgy personality, I decided) spared a glace first at me, then followed my gaze. “The firewood?” he asked softly.

I nodded my head. “Cellulose, actually. The basic chemical formula, you must know, is C6H10O5.”

C six?”

Again, I nodded. “I’m afraid so.”

My client shivered. I rose and, with my matchbox, descended to the fireplace, where I expertly set the wood on fire. “Now, sir, I’ll have you know, this Carbon of yours is being released out through my chimney.”

He was still shivering as he looked up towards the ceiling.

Try to stay calm. This won’t be easy.” I came back and sat down next to the molecule, who looked rather taken aback. “I added the amount of energy from my matches needed to start the combustion reaction, properly stated as C6H10O5 + 6O2 coverted into 6CO2 + 5H2O. The water vapor, that’s the H2O, and the carbon dioxide, that’s the CO2, the one we’re interested in, are not making their escape into… the atmosphere.”

Th-this all came from the wood?” asked my client.

I nodded. “And the oxygen in the air.”

And where will it go now?”

I took a moment, got up, and walked to the window, unsure how to break the news. The moon, full and shining, lit up the countryside outside my window, and I could see the vineyard that was stationed just outside our curious city. The molecule got up and followed me.

What is it?” he asked quietly.

I pointed to the grapevines outside. “You see those plants. They are made of glucose, a carbohydrate—a sugar, rather. You know the formula, I suppose?”

My client nodded to me knowingly. “Yes. C6H12O6.”

That’s right. The plants get the carbon, and the oxygen, from the carbon dioxide… in the air now around us.”

I knew he couldn’t take this lightly. As he looked faint, I helped him to his seat. “It’s called photoshynthesis,” I said, trying to calm him. “Without it, we would have no fuel, no food to eat. The exact process is 6CO2 + 6H2O converted into C6H12O6 + 6O2. Plants release the oxygen, somehting humans and other animals take in.” The talking seemed to do my client good. I was comfortable enough to leave him and get some wine. I poured him a glass and me one as well. He looked grateful for the treat. As I sipped mine I side, “Carbon is in this too, I’ll have you know. Wine comes from the fermentation of grapes, which makes ethanol, the ‘drinking alcohol’.”

Ah, yes, I’ve heard of that,” he told me. “Isn’t the chemical formula for ethanol C2H5OH?”

Yes.” I concurred. “The precise reaction is C6H12O6 converted to 2CO2 + C2H5OH. But I haven’t told you everything yet.”

My client was anxiously watching me. “What is it?”

I got up from my seat, bracing myself should he feel faint again. “There’s also cellular respiration.” The room was as silent as the night outdoors. I took a deep breath. “Animals are made of glucose, among other things. We get it by consuming grapes and other foods. It’s the reverse of photosynthesis, and it keeps us connected to our green, leafy friends. The process is C6H12O6 + 6O2 converted to 6CO2 + 6H2O.

So now you see, Carbon is everywhere, sir. I hope I have helped you. Now sir, if you please, I have some work to which I must attend.”

The molecule gradually got up from his seat and started to leave. At the door he stopped and said quietly over his shoulder, “I should thank you, Bennett.”

Thank Carbon, sir. Thank Carbon.”