Chemistry 21,22 questions!! Velocity!

Mixture: 1 6 7

Elemental: P O2

Compounds: NH3 NH4HCO3

Oxygenate: NH4HCO3

Oxides are: None.

Combustion = 2p2o5

Write heat and mno2 up and down the equal sign

There is a light on it on the equal sign.

Ignite ====Fe3O4

Question 22: (1) It should be red phosphorus. Phosphorus + oxygen ———ignition, this is written above) phosphorus pentoxide.

2) Potassium chlorate ——— manganese dioxide, write above. Write the meaning of heating below) potassium chloride + oxygen.

3) Sulfur + oxygen ———ignition, write above) sulfur dioxide.

4) Iron + oxygen ———ignition, write above) ferric oxide.

Visually I wrote it into a literal expression.,The landlord himself changed it to a symbolic expression.。。 21 questions The person upstairs has already written the answer, I will help you write 22 questions, help you write them out the symbols, phosphorus p oxygen O2 potassium chlorate kclo3 mn sulfur s iron fe

No. As for hydrogen peroxide, it should be a mixture, and I haven't heard of pure hydrogen peroxide, because hydrogen peroxide refers to an aqueous solution of hydrogen peroxide.

22 I forgot.

It's simple, you write it yourself, that's the basics.

Where are you in the third year of junior high school? It's like high school, and it's okay. Medium potassium hydroxide drops into aluminum chloride, and there is a white precipitate. Aluminum chloride drops into potassium hydroxide and has precipitated but dissolves quickly. Based on this phenomenon, it can be judged whether it is potassium hydroxide or aluminum chloride.

The first group can be distinguished with high school knowledge: the three solutions are dropped into each other in small amounts, and two by two produce the precipitated AlCl3 Koh, and the other is Na2SO4 to divide the precipitate of the first reaction into two parts, and add the other two solutions except Na2SO4 to each other until the excess is excessive. The precipitate that produces and the precipitate does not dissolve is AlCl3 is added, and the precipitate is continued to produce the precipitate first, and then the precipitate is dissolved by adding Koh, because the excess KOH reacts with the precipitated Al(OH)3 to form soluble Kalo2.

NaHCO3 in option B is indistinguishable from H2SO4, Option C is indistinguishable in 3, Ca(OH)2 is indistinguishable from BACl2 in D This question Choice A I don't know if it's right Hehe.

The mass fraction of calcium in calcium carbonate is 40 100 = 40%.

Adults are supplemented with calcium every day, then the calcium carbonate quality is.

Take 3 tablets daily.

Do it with the difference in the amount of travel Qi shooting method.

Before and after the reaction, the amount of solid mass decreases ==

H2 + Cuo == High temperature == Cu + H2O mm

80/m = 16/

m = so cuo quality is.

The CU mass is - =