Defect another world

Chapter 551 Brilliant Murder
"What's missing? It doesn't seem like there's anything missing, right?"

Fatty Chen has already sifted through everything that should be in the plastic bag from the perspective of eating and drinking.

"Ziploc bags, meat, bamboo skewers, cans and drinks in cans. Nothing else."

Judging from the plastic bags they were carrying when shopping, getting in the car, the plastic bags that Mo Sheng's family were carrying at that time were no different, and they didn't lack any of them.

But something is invisible to you.

Obviously they are very important, and they are right in front of your eyes, and you throw them into the trash can with your own hands, but afterwards you can't remember that they ever existed.

"You just remember to eat and drink. In fact, there should be another very important thing in the plastic bag, and that is the ice pack."

Meng Fei patted Fatty Chen's fat face, which was a little dazed because of his hard thinking.

"Tourists usually buy it at noon and eat barbecue at night. If they are left for an afternoon, although it may not necessarily stink, the taste will change somewhat.

"The so-called original ecological barbecue in this place is very particular about the taste. Therefore, when the meat is sold in the supermarket, there must be a lot of ice packs."

Meng Fei was very impressed by this.Because he was carrying the bag at that time, he felt it was very heavy.In addition to the drinks, the ice packs accounted for several kilograms.

"In this case, after the vehicle fell into the water, the ice pack could not have disappeared for no reason. Why was it not found?"

Those ice packs were completely sealed in plastic wrap.Otherwise, once the ice cubes melt, water will flow everywhere.

The ice pack is not entirely ice, but a gel-like substance that absorbs water easily.Freeze in a plastic bag after soaking up water and keep it cold for a long time.

Even if the vehicle is soaked in water and the ice in the ice pack melts, the ice pack itself cannot disappear.But the truth is, none of the ice packs in the plastic bags are gone?
"But it's not surprising, is it? If there is no ice pack in the supermarket, there is no way to give it to them. Besides, what does this have to do with the car falling into the lake?"

Chen Han still didn't quite understand.

"Think about it, this car is called a sleep bus."

Meng Fei squeezed the soda can in his hand, hesitating whether to enjoy the refreshing feeling of the cold drunkenness passing through his throat again.

Thinking about how alcohol promotes various changes in genes, leading to nasopharyngeal cancer, esophageal cancer, gastric cancer and intestinal cancer, he put it down again.

"In addition to the comfortable deck chairs, the quiet and monotonous scenery, the soft and comfortable road surface, and excellent sound insulation, there is actually another important factor.

"I saw that all the windows were closed, including the window on the driver's side. And the air-conditioning was recirculating.

"Because this sleeping bus is actually not very big, the interior space is small, and the ventilation is not very good, so the oxygen content will drop."

"Oh!"

Fatty Chen patted himself on the head.

"You mean that the people in this car were actually suffocated to death by the car?"

"No no no."

Meng Fei quickly shook his head.

"Even if the windows are closed, the car is ventilated. The internal circulation of the air conditioner only reduces air exchange, not completely closed.

"It's just a slight drop in the oxygen level in the car that makes people feel sleepy, and it's absolutely impossible to suffocate. Otherwise, it's not a sleep bus but a death bus!"

"Then why did the driver faint?"

"It would be dangerous if the oxygen level in the car could be quietly dropped and the carbon dioxide concentration kept rising."

Meng Fei imagined the scene at that time.

"The concentration of carbon dioxide in normal air is 0.03%. When it reaches 1%, people will have difficulty concentrating and feel sleepy.

“Poorly ventilated offices can reach 2%, causing employees to feel sleepy, mentally fatigued, and less productive.

"If the concentration of carbon dioxide reaches 5%, people will lose consciousness and lose their minds.

"While a short period of time is not necessarily fatal, on a long road with water on both sides, it is almost safe for the driver to drive the car into the lake.

"In this way, all the people were temporarily unconscious due to suffocation caused by carbon dioxide, and then fell into the lake and drowned.

"The autopsy analysis showed that the cause of death was pulmonary edema caused by hypoxia. It is difficult to distinguish whether there was a coma due to carbon dioxide before drowning.

"And carbon dioxide, of course, will disappear completely after being soaked in water, and there will be no trace of it in the test."

"Carbon dioxide? But where did the carbon dioxide come from? Did someone completely block the vents of the car?"

"Don't block the vents.

"There is something that can continuously produce carbon dioxide, and no one will doubt it when you bring it into the car, and there will be no traces afterward."

Meng Fei pretended to be mysterious and said.

"I know what this is."

Fan Bu's eyes lit up.

"It's dry ice!"

"Ah."

Meng Fei nodded.

"Generally, supermarkets that buy and sell this kind of meat ingredients will have a lot of dry ice to keep the food at a low temperature during transportation.

"Edible dry ice is in the shape of a cylinder or a block, and it can be mixed with ingredients, and the effect of keeping low temperature is much better than ice packs.

"The murderer did this: when Mo Sheng and his family came to buy meat, they pretended that the ice pack was gone, and replaced it with almost the same amount of dry ice.

"Dry ice doesn't need packaging. It turns into gas and expands. If the package is closed, it will expand and explode.

"When it turns into carbon dioxide, it disappears. If it is soaked in water, it will turn into gas faster, and it will not leave any traces in the car afterward. The only clue is that the big plastic bag with meat ingredients is not there. ice bag."

Then Meng Fei started his "second calculation" process.

"Visual inspection of the sleeping bus we have taken is about 6 meters long, 2 meters wide, and 1.5 meters high inside, so the volume is 18 cubic meters.

"At one standard atmospheric pressure, after one kilogram of dry ice is converted into carbon dioxide, the volume is about 0.5 cubic meters.

"The three of them bought a total of about six kilograms of meat, and the amount of dry ice added is estimated to be similar to this.

"If it is six kilograms of dry ice, converted into a volume of 3 cubic meters, the carbon dioxide concentration in the sleeping bus can be increased to 3/18, about 16%, which is a proper suffocation.

"But the sublimation of dry ice into carbon dioxide is a slow process. And the car is not completely ventilated. It's like boiling a frog in warm water, and it's hard for people in the car to notice.

"So about an hour after the bus departed, when the carbon dioxide concentration reached between 5% and 10%, both the passengers and the driver passed out and fell into the lake.

"If it's murder, it's really wonderful!"

　I have to rest for a while later, and I have to change the map again, pit...

　　
　
(End of this chapter)