Two very weird questions from a chemical point of view!

1.Because the fire is generally combustible, the tools that are available or in use are oxidized to carbon dioxide, and the tools cannot be used, which is a loss, so people will become sad;

2.When burned, a large amount of carbon dioxide, carbon monoxide, sulfur dioxide and other gases will be produced, which may suffocate people, so people should stay away quickly. In addition, when burning, the surrounding oxygen will be consumed, and without oxygen, people may lose their lives, so hurry outside to breathe fresh air.

1. Substances with use value are on fire, and after chemical reaction, the products are substances with use value. It's too late to worry!

2. The fire site generally undergoes a chemical reaction to generate a large amount of CO2 and toxic gases. CO2 can suffocate people, and toxic gases can poison people. Running away from danger is an instinctive human reaction.

1. Because of the fire, it means that your things are burned, and if you burn them, they will be gone, who will be happy.

2. Because the smoke generated can kill people ......

What grade are you in? What are you studying?

Under the standard condition, a gaseous hydrocarbon is 112ml, the amount of its substance = the combustion product through soda lime, the mass of soda lime increases, this is the mass of CO2 and water, according to the volume ratio of carbon dioxide and water vapor is 3:4, it can be calculated that their mass fraction is: CO2 is 44 * 3 (44 * 3 + 18 * 4) = 132 204; If H2O is 18*4 (44*3+18*4)=72 204, then the gram of CO2 and the mass of CO2 in water =, the mass of water = , the amount of carbon in 112ml of gaseous hydrocarbons =

Amount of substance containing hydrogen =

The number of atoms containing c in a gaseous hydrocarbon molecule =

The number of atoms containing h in a gaseous hydrocarbon molecule =

So the chemical formula of gaseous hydrocarbons is mainly C3H8

To supplement the upstairs, ammonium sulfate is used as fertilizer to supplement a large amount of nutrient nitrogen, but also to supplement a medium amount of nutrient sulfur.

1.2NH4HCO3+H2SO4 = (NH4)2SO4+2H2O+2CO2 (add an up arrow).

2.The density of CO2 is higher than that of air. Therefore, it needs to be placed in a high place to facilitate the absorption of crops.

3.(NH4)2SO4 contains ammonium ions and sulfate ions, which can be applied as nitrogen and sulfur fertilizers in rural areas.

2NH4HCO3 + H2SO4 = (NH4 )2SO4 + 2H2O + 2CO2 Note that CO2 should be represented by an up arrow.

2 That's because CO2 is heavier than air, and placing it in a high place is conducive to the uniform distribution of CO2 throughout the greenhouse and improving the utilization rate of carbon dioxide.

3 Ammonium sulfate can be used as a nitrogen fertilizer.

In the first question: I think that pH test strips are not a substance...And litmus belongs to a pure substance, and the composition of the pH test paper should be thymol blue. Methyl red. Bromocresol green.

The second calcium hydroxide belongs to one of the four strong bases....If you use clarified lime water. There is no guarantee that it will be completely neutralized. If you put more alkaline, put less hydrochloric acid is not completely neutralized and the limestone solubility is poor, you can add too much

Third, potassium hydroxide has a greater molar mass than sodium hydroxide. This is the case when waiting for quality. Potassium hydroxide has a low number of molecules....Now it's time to make sure you get neutral potash. Then the number of molecules of KOH must be increased, that is, the mass of KOH must be increased....Therefore, the flow valve is enlarged.

Another: I don't think upstairs is correct about the sensitivity of test strips. In real life, as long as the solution is concentrated in OH, there will be obvious discoloration.

1 d (probably because the pH test paper should be added to the color card line) 2 A 3 The valve should be adjusted smaller (the ratio of potassium hydroxide and sodium hydroxide to sulfuric acid with the same mass fraction is 10:9, and the specific process is inconvenient), I haven't looked at things for a long time, it may be wrong, just for reference!

The first question, the pH of sodium hydroxide in the pH test paper and the color of the water can not be checked, it is difficult to distinguish with the eye, the second question, calcium hydroxide is weakly alkaline, and the reaction with hydrochloric acid is incomplete.

The third question, write the equation of the chemical reaction, balance the two sides, and you will find out.

1) Broken glass instruments.

2) Heavy metal ions will cause pollution, and those containing strong acids and alkalis will corrode the sewer pipes 3) Condensate reflux will cause the test tube to burst.

4) The glass rod may be broken.

5) Upward exhaust air that dissolves in water and is denser than air.

Downward exhaust air that dissolves in water and is less dense than air.

Insoluble drainage of water.

Chlorine gas is discharged into saturated salt water.

1.Excessive pressure in the bottle can cause the bottle to break.

2.There may be contaminating or poisoning substances.

3.The liquid inside the bottle may spill out and shoot into the person's eyes.

2.Damage the glass instrument or glass rod. (You can't afford it.) 3.When collecting, it is necessary to pay attention to whether the density is greater than that of air and whether it is soluble in water, and the collection device can be used according to the nature of the gas.

When storing, pay attention to whether there will be a light reaction, and whether the air is going to be dry.