Chemistry The following methods of extinguishing fires are incorrect

a: Extinguish the oil pan with a lid when it ignites.

Yes, isolate air (oxygen).

b Pour alcohol on the lab table and catch fire, extinguish with a damp rag.

Yes, the air is insulated, and the rag absorbs some of the alcohol.

c. Gas leakage and fire: Close the valve immediately and open the window for ventilation.

Yes, isolate combustibles and ventilate some toxic gases.

d Electrical appliances caught fire and extinguished with water.

Wrong. Water conducts electricity, which can easily cause the danger of high voltage.

Solution: a. According to the liquid carbon dioxide fire extinguisher, it can be used to extinguish the fire of books, archives and valuable equipment, precision instruments, etc., so the library materials are on fire, and the compressed carbon dioxide is used to extinguish the fire, and the suffocation method is used to extinguish the fire, so the fire extinguishing method is correct;

B, according to the principle of fire extinguishing: destroy a condition of combustion to stop combustion, you can achieve the purpose of extinguishing fire, when extinguishing forest fires, set up isolation belts, use the isolation method to extinguish fires; Therefore, the fire extinguishing method is correct;

c. When the oil pan catches fire when stir-frying, immediately cover the pot with a lid, and use the suffocation method to extinguish the fire, so the c. fire extinguishing method is correct;

d. Electrical fires cannot be directly extinguished with water, because water has a certain conductivity, so the fire extinguishing method is wrong

Therefore, choose D

d Water is a conductor, so water can pass through, just turn off the switch.

d is incorrect. Because water is a conductor, extinguishing it with water can cause an electric shock.

d. There are many reasons for electrical fire, it can be caused by overloaded socket or UMC.

D is definitely not right. The power supply should be disconnected first. Water used in daily life is a conductor.

Is the method of extinguishing the fire right?

a.When extinguishing oil fires, use a chemical foam fire extinguisher and then use a BC dry powder fire extinguisher.

b.When extinguishing Class E fires, use a BC dry chemical fire extinguisher followed by an ABC dry chemical fire extinguisher.

c.When extinguishing a combustible gas fire, use a carbon dioxide extinguisher followed by a BC dry chemical fire extinguisher (correct answer).

Answer]: Noisy d

Chemical inhibition fire extinguishing method refers to the chain reaction of inhibiting the generation of free radicals or reducing the concentration of free radicals in the flame and interrupting the combustion chain reaction by making the fire extinguishing agent participate in the combustion reaction process. The fire extinguishing measure is to spray heptafluoropropane, hexafluoropropane fire extinguishing agent or dry powder fire extinguishing agent on the combustible material to interrupt the combustion chain reaction.

Answer] :d chemical inhibition method refers to the participation of the fire extinguishing agent in the combustion reaction process, inhibiting the production of free radicals or reducing the concentration of free radicals in the flame, and interrupting the combustion chain reaction. The fire extinguishing measure is to spray heptafluoropropane, hexafluoropropane fire extinguishing agent or dry noise trapped powder fire extinguishing agent on the combustible material to interrupt the combustion chain reaction.

Answer]: then start C

This question examines leakage control and destruction techniques. For magnesium powder, aluminum powder and other dusts, do not spray pressure fire extinguishing agents, in case the powder is blown up and caused by dust.

Tong Suma Answer] Game Fight: C, D

Fire extinguishers should not be installed in places that are not easily detected and in the dark. The fire extinguisher should be placed securely and its nameplate should be facing outward. Portable fire extinguishers should be set up in the fire extinguisher box or on hooks and brackets, and the height of the top from the ground should not be greater than l 50m; The height of the bottom from the ground should not be less than 0 08m.

The fire extinguisher box should not be locked. For fire extinguishers with obstruction of sight, illuminated signs should be set up to indicate their location.

Test Center**] page 361 of the textbook "Fire Safety Technical Practice" of Youcong.

Answer] :d Whether it is a portable fire extinguisher or a cart fire extinguisher, the operating procedures used for fire extinguishing are the same, fire extinguishing operation steps: obtain a fire extinguisher and move it to the fire extinguishing site; Remove the safety device, and the seal will be automatically destroyed; Open the bottle valve of the fire extinguisher; Aiming at the fire source, the wide jet is used to extinguish the fire.

At present, all Huichong fire extinguishers cannot be used upside down. Therefore, choose D

Answer] :d This question examines the fire extinguishing mechanism of dry powder fire extinguishing. Two-line macro carbon oxide fire extinguishing mechanism:

The first is suffocation, followed by cooling. The fire extinguishing mechanism of the foam fire extinguishing system: oxygen isolation asphyxiation, radiation thermal resistance or ruler separation, endothermic cooling.

Fire extinguishing mechanism of dry chemical fire extinguishing system: chemical inhibition, isolation belt height, cooling and room breathing.

Answers]: a, d, e

Carbon dioxide fire extinguishing agent can extinguish gas fire before extinguishing the fire, liquid fire or paraffin, asphalt and other meltable solid fires, solid surface fires containing holes and cotton, wool, fabric, paper and other solid deep fires, electrical fires. Second, the carbon oxide fire extinguishing agent shall not be used to extinguish the fire of chemical products containing oxidants such as nitrocellulose and gunpowder, the fire of active metals such as potassium, sodium, magnesium, titanium, zirconium, etc., and the fire of metal hydride such as potassium hydride and sodium hydride.